I wasn't opposed to the idea of MP 1 + 2 on a single disc when the wiimakes were first mentioned, hell I think I even had my own topic on it or at the least started a discussion of it in the MP3:Corruption thread.
As for the way you're putting it, Vega, I actually wouldn't want a full online mode. It'd be a nice addition, sure, but I'd much rather have extra content in each game over an online mode I wouldn't use. I'm not the most diehard Metroid fan and even I know Metroid isn't about multiplayer, so including it would feel just as out of place as it did in Echoes.
As far as fetch quests go, I don't care either way. I found the majority of the keys/artifacts along the way, and the few I didn't find were enjoyable to go after because they were pretty tough. At that point in the game you think you'd searched every nook and cranny there is and it drives you insane that you can't find that ONE LAST FREAKIN KEY.. but it just pushes you further to find it because its such an accomplishment when you do... Or in contrast it was so easy that you feel stupid for overlooking it and have a laugh at your own expense. But these are things games are made of. Oh wait, I forgot.. in this era of games we all want instant gratification, oh well guess I guess I enjoyed something I wasn't supposed to, D'oh!