While I would disagree that MP started off "slowly", I will agree that it did pick up. I would also agree that Echoes started off faster, but in my opinion slowed down a LOT towards the end.
SPOILERIFIC impressions. Don't read unless you have indeed beaten the game. Many new power ups, and almost all bosses will be talked about. Again, don't read unless you really want to spoil the game.
When I first started playing Echoes, it was in a party fashion. The majority of the people there were huge Metroid fanatics, and those that weren't quickly converted. The fog and the atmosphere set the mood perfectly. The game may have felt a little slow due to the amount of scanning to be done, but due to the atmosphere already set, that didn't matter. You were in a new game, and it was screaming "I rock, and you know it." Everybody at the party had a huge grin on their face the whole time. Twas sweet.
After the party got over, I plugged away until I got the dark suit. The boss fight with the 6 worms before that was simply amazing. Possibly because I had been away from the MP controls long enough to have forgotten some of the subtleties or what, I don't know. That battle was intense, and just gobs of fun. After getting the suit, it was enough for one day.
I played again the next day, and died for the first time at the boost guardian. The death sequence was most definitely improved, and I loved it. After playing a good portion of the day, I went to bed after fighting the Chykka. Again, talk about a sweet boss. I didn't die on it either, but it was most definitely intense. I absolutely loved it.
I started playing some yet again the next day, and entered the last section of the game, the fortress. The Aezbit effect was most definitely cool, but ultimately they were just lame and took too long to kill. I was impressed with this level through and through in the design aspects, but didn't enjoy playing it so much. I thought it was neat, and an interesting turn for the Metroid series when I first saw it, but I wouldn't go back just to "take it all in" like I could, and probably will do with the rest of the sections in the game. The boss fight at the end against the machine was lackluster compared to the other two, and that was sad, considering the talk of all the awesome bosses beforehand.
That is the mark I think the game took a turn for the worse. I don't know what exactly made it that way, but it did. Apparently, because no reviewers wanted to spoil the end of MP and say that they didn't enjoy collecting all the artifacts in the other game, that Retro thought that was a good idea to do it again. Wrong. Those would have made for sweet secrets, unlocking art pieces, characters for multiplayer, or whatever, but making the collection of 9 keys over the world was a pointless chore. I did get through it in a timely manor, and even got some before I was sent out to them, but it most certainly wasn't "fun" to go and get them all.
Again, a big differing point for MP. After collecting all of the artifacts, you were treated to one of the best boss battles in the game, if not "the" boss battle. It was most definitely my favorite: Meta Ridley. Here, we go to the dark version of where the luminoth was, and we get another lack luster boss battle. I died a total of 1 times on the emperor vs the probable dozen I died on MP (I didn't die on Meta Ridley, but I sure came close). The battle wasn't difficult, you just had to stay alive long enough to hit his hands off, then charge your light beam a few times and hit him. Not a challenge. The ball part of him gave you all your health back too if you wanted it.... Sure, the boss looked impressive, but most definitely didn't compare with the others at the end of the original, or even the first 2.
The fight with Dark Samus was a joke. A complete joke. The only reason I died is because I ran out of time due to not scanning her 4th version (I missed the change from version 3 to 4). At the time I was glad to see that I didn't have to fight the Emperor again, but in actuality, I am disappointed. I feel that if you were able to endure that many version of the Emperor, and Dark Samus is that easy, that you should have been forced to do both on the same try. Just my thought.
I didn't finish the original Metroid, but I can only imagine its final boss fight. I can't imagine it being easy. I have played through all the others countless times, and the final boss was never a push over. How many times did you die to the Queen Metroid at the end of Metroid 2? Exactly. The boss battles in prime 2 were only outdone by the ending.
For me, there are subtle things that make up metroid games. Firstly, there is a sense of aloneness. I was willing to forego that in this game, by getting missions from the luminoth, so I didn't mind there being other people. Secondly, the simple exploration and back tracking. This game nailed it. I would get stuck in an area and just think back to the last game that is happened in, and guess what, it was a metroid one. It simply rocks, and Echoes captured it wonderfully. Many people would argue platforming is a big part as well. Personally, I don't find it necessary, but they nailed that as well to, so kudos to them. Then, it gets a little bit more dicey, but personally, I have a few reserves. Death sequences since Super's have to be awesome. They kept that up, and boy was I impressed this time. Most definitely cool. Next would be the last 5% of the game. That would include the final boss fights, and the ending. Well, you already know how I feel about the final boss fights here, so the ending has to be good, right? I only wish. Seeing Samus type into her gun, and jump off the crater entrance in MP was just sweet. Seeing her take her helmet off was cooler, and seeing the Phazon suit being ripped off and coming up again was much cooler. What do we get in this one? Well, after beating it with 80 percent, I should have at least got something comparable to the first 2, much as you would have in the original. Nope. Samus waves good bye to the Luminoth, takes her whole suit off, looks like a CARTOON (what happened to the model they used last time? Her face at least looked good then. Her face looked good through the visor in this one, but fully revealed looked remarkably dumb. I laughed and couldn't believe they actually released it), and casually boards her ship. What happened to the coolness factor bubbling over in the rest of the game? I wish we had a collectors edition DVD in which we could get an explanation as to why they had to do that, much like Halo 2 has.
As soon as I finished the first prime, I immediately started over on hard. My jaw hit the floor so hard after seen Samus get squashed by the Elite pirate, and the final boss fights were just awesome, I had to see them on a higher difficulty. This time, I finished, and had no immediate desire to start back over (I do now, but don't know if I will actually have time).
I beat it in 17 hours with 95% scans, and 82 percent collected. Where was the "longer and more challenging" game they promised? It took me closer to 30-40 hours to beat prime, taking my sweet time, getting around 50 percent scans and 69 percent of the items.
All these impressions make it sound like I didn't like the game at all. Not true. I loved it...for the most part. The underwater jet upgrade rocked, the screw attack rocked, and the new suits rocked (even though IGN's review spoiled the last suit. Now I seriously loath IGN), but after the 3rd boss, things seemed to take a turn for the worse, rather than get better, like most metroid games do. Remember the SA-X? Remember the terror involved in facing it? What happened to that? I was hoping/expecting the same thing from Dark Samus, but all I got was a push over boss all 4 times. Now I am curious to play through the game on hard, just to see if that terror can indeed be put in place. I don't like the idea of having the "real" version (hard mode) be the un-lockable one. Next time, it should be selectable from the start, so the game can be played the way it was meant to be played.