What job to play? please advise

[Xehmnus]

I mean... I remember playing EQ2 and the amount of skills doesn't really seem all that different. Maybe just me though?

As for SAM... the buffs/debuff are part of your basic rotation so it's really not hard to keep them up and active, especially considering their duration. The additional skills you'll get on the way to 70 may well seem a little off-putting at first, but it comes pretty easy once you start getting them. Also, having all of 2 positionals, which only matter for kenki generation purposes, REALLY isn't bad.

I have no experience with DRG, so can't really help you there. NIN, on the other hand, is actually pretty fun. All of 1 debuff to keep up, then Trick Attack (which is awesome) and then just using jutsus and resource spenders on cooldown.

MNK can be fun too, though if positionals bug you on SAM, you REALLY won't like them on MNK. So... there's that.

As for the cooldown thing... eventually, you'll just get used to the timing of when they're up. You can, if it helps, set up a hotbar with the icons relatively near your character on the screen so they'll be easier to notice when they're off cooldown. Alternatively, you can set them up as macros with wait timers lasting for the cooldown time and set them up to say a message/sound effect when they're off cooldown.