General

@Vigorous: it's been a while since i played mines but at the beginner skills list, the passive 'sunfire'(i think that's what it's called) you'll deal an extra 50% dmg + 1% of max hp

totally not bias battlemage

Demon Slayer.

A decently funded Shad can dodge almost always at SH. Plus, even if you do get hit, a shield will almost double your weapon/magic defense and meso guard reduces damage taken in half (the cost is negated two fold because Shads collect mesos so easily that an additional small profit can be made training). Shadow shifter gives you an additional 45% avoidability rate. Shads can heal use the move steal, which at SH drops potions that are consumed immediately when picked up and give +30 ATK and fully recover HP/MP (mostly useless because Shads don't get hit often nor do they take much damage from hits).

For training, just macro boomerang stab and savage blow, and you should be fine. As for bossing, Shads do decently, just spam assassinate and watch the HP go down (KMS recently got an update that makes assassinate extremely fast).

The cons? Thieves are generally expensive to fund.

buy a pet

Kaisers are a warrior class so they have naturally high def and hp.
They have a 3rd job skill that gives a % of max hp back every few seconds, And if you use a skill via the combo input (Stupidly easy to do) you get a bunch of health back...
blade burst is your main mobbing skill at 4th onwards, deals massive damage to a bunch of enemys in a wide area.
Giga wave is your main bossing skill at 4th onwards, Low damage per line but deals a lot of lines very fast. Although due to this you need a bunch of funding to do decent enough dps, but once you start doing 300K+ damage to bosses with each line of giga wave you can do all kinds of bosses.
Plus i think the story's good ;3 And i've actually had somebody in my party before who was impressed by how flashy the skills were (Especially that final transformation).

Battle Mage. Massive HP plus you have drain, and drain + twister spin = Never run out of HP

Paladin Kaiser Battle Mage or Demon Slayer

If you like to sit back and relax you can do Kanna and at 3rd job use Kishin. If you get it maxed you can press the skill button every now and then and go watch some anime or something.

Luminious' Sunfire skill heals 1% of your max hp with every light attack you do while in light mode.
All skills will do that while in equilibrium.

@FreeIcecream @Jlemaster I am definitely considering them.
@Raiden Is it really that bad?
@Gaosaurusx3 How exactly do you heal?
@RubberDonkey I like Shade but I dislike how miniscule the heal is

Islander.
It's very tanky against pigs, you don't even need to heal, and you can solo mano whenever you want.

dude make a luminus and get a jr boogie familier,
i RARELY use an mp potion or hp potion and after lvl 100 u get an awesome mobing skill

Chars That Heal on attack :Battle mage, aran , Demon slayers (kinda) drk nice option
Chars that Are pretty tanky Lumi , shade nothing else i can really think off i mean could also go high Avoid route and pick phantom o.o

Dark Knight!

Battle Mage or Dark Knight.

Dark Knight.
No explanation is needed.

battle mage would be the best option, but it isn't exactly laid back. you have to alternate between your main attacking move and the 170 hyper, which takes button smashing, unless you are very skilled at the class.

demon slayer is pretty good too.

Shade is really carefree. Don't need to buff, no chaining, free revive, one main attack, heals on hit.

demon slayer is laid back as heck

yeah, luminous would probably be a good choice, heals depending on your state of element(light/dark) great dmg, great mobbing, lots of mp o3o

Battle Mage comes to mind. Don't let the fact that it's a mage throw you off. Great bosser after 170 and I haven't died as one. Bulkiest non-warrior class.

Eric.

Luminous.

Aran recovers a lot with combo drain.

You're going to be mashing buttons a lot so not exactly relaxing though.

Battlemages are quite bulky, and they drain hp with each hit.

You described Paladin

Lol.... go hack