The game isn't just about slashing enemies to kill them, some of them require more that just slashing them, as in hitting their attacks back at them, or even hitting some enemies back so they take out enemies you can't reach.
The game is on rails, only in town to you have full control of where you can walk, in the field you can go forward and backwards and very little bit you can look to your left or right. By default the you will slash around the middle of the screen but you can select anywhere on the screen where you want to slash, which is what you will need to do to get the enemies out of the default line of attack. You defend with your shield (B Button) and your shield does wear down and break up as you use it, but it's not a real quick thing, and you can buy/find item to fully replenish your shield.
Leveling up is easier/quicker than normal Dragon Quest games.
You can only change equipment in town, so if you find some new stuff in the field you might want to go back to town and change it, the only penalty is having to play the level again, which isn't a big thing because if you complete a level and come back it's like playing it again fir the first time, except the treasure chests don't replenish themselves like they did in Joker (at least I haven't found any that did)