DQ V is the best, IMO, even though it has the fucking gayest name ever chosen for a video game "Dragon Quest V: Hand of the Heavenly Bride".
3, 4, 6, 8 are great. 7, & 11 are good. 1 & 2 are just too old school for me to enjoy, but I have yet to play the Switch releases.
I liked 11 because it was such a mind fuck:
You try to save the world, only to find out you were helping the bad guy all along, who promptly uses your efforts to fuck the entire world like no tomorrow. You eventually stop him, but genocide has already happened, so, LOL. You then go back in time, leaving all your friends in this world you have genocided, to try and stop the genocide, but it won't actually help the friends you left behind, because that branch of reality has already happened (nice nod to the multiverse theory). So, you manage to stop the 'big bad' from raping the world, but in the process you enable the 'bigger bad', which you find out was left behind for you to deal with in the present by a bunch of ancient fuck-ups who couldn't get the job done, to come back and rape the world his way. Eventually, you are able to destroy the bigger bad. Subsequently, you help the bitch from the previous group of ancient fuck-ups that tried to save the world and only partially succeeded and left the 'bigger bad' behind so it was your problem in the present, to go back to in time and get a chance to stop the ancient group of fuck-ups from fucking up in the first place. However, her going back, just like you did, won't help you at all, because multiverse again. Given how things have gone thus far, I wouldn't bet that it went all that well for ancient fuck-up bitch since everyone in this game appears to be a hardcore fuck-up retard.
TL;DR - You end up fucking the entire world with genocide, you eventually stop the fucking from continuing, but LOL, genocide can't be undone. You abandon your friends in genocide world to go back and try to stop said genocide, even though it won't actually help them since LOL multiverse. You stop genocide, only to allow an even bigger bad guy to fuck the world instead. You eventually stop the bigger bad and unfuck the world, which wouldn't have been fucked if you had just fucking stayed home and never done anything. You are an abject failure of a hero and should have committed sudoku at the beginning of the game and everyone would have been better off, but no one would pay $60 to spend 5 minutes to become the an hero