5 advanced jobs changes:

Paladin
change cover to a stance and available level 1 and change it so that allies behind the paladin receive damage taken II – 5%-10%(item+ while activated) whether they have enmity or not and increases the paladins parry and shield block rate as well at tactical tp gained from blocking or parrying. (good for fights the whole party needs to stand close)
Change Rampart to be a stance it increases the paladins magic and physical damage resistance, parry and shield block rates, +Enmity,, haste penalty (good for tanking when only pally is in range)
Change crusade to be a stance that adds Spellcasting/recast speed, spell interruption down resistance, and bonus damage to all light/holy element spells. Generates TP on successful magic burst with these spells. Available at 49 as a subjob ability.( Holy damage, burn for old school bones stuff)
Change Majesty to a stance and make it available at 49 (rdm needs this to main heal, and separates them still from WHM and scholar because they have to remain closer to the party)
Paladin needs more access to clubs and hammers. It needs an endgame viable mace/club/hammer
Paladin could use more access to Greatswords built around parrying and tanking like Runefencer.
Lastly Paladins need more accuracy in their tanking stance and should maybe benefit more from actually engaging the monster(add some effects to their weaponskills that help them tank)

Dark Knight:
Make last resort a stance (can’t be dispelled lasts longer than cooldown)
Change soul eater to be a stance that enhances how much MAX hp and how much healing Dread spikes can do(heals more than it damages) and shorten dread spikes recast to be able to keep it up.
Keep them both available from subjob.
Move Nether void to level 1 keeping with the elemental seal mechanic that each job has one at level 1 that can. Move dread spikes to level 49. If you want, make a better version of dread spikes for level 99 DRK but dread spikes 1 should be good enough to consider for tanking on any magic centric tank like PLD or RUN
Add the max HP increase effect to all versions of Drain just let it scale higher on drain 3 and keep drain 3 DRK specific.
The game needs more viable tanks point blank and MNK and DRK take the least amount of work to get there.

Beastmaster:
I am at a loss really for where the design is supposed to go per the creators vision Beastmaster has been all over the place for as long as I’ve played and doesn’t seem to keep a clear vision for very long. but I have a suggestion:
Create 2 stances, one for the Beastmaster being the priority for DPS and them using a support pet with a cool buff and/or debuff. Make a second stance where the Beastmaster can stay further away and it super buffs the pet. This way you can balance each aspect of Beastmaster separately without affecting each other.
Remove dependance on jugs from the game, just make it so you have to collect the jugs one time to add them to your list of summonable beasts make them KI’s
The way I see beastmaster is it and DRG should both be very close to “Partners” as pet jobs I think both jobs could benefit from a reward system when you successfully skill chain with your pet, like maybe when you close a skillchain from your pet opening it reduces the cooldown for the next ready action, and if the pet instead closes it gives you tp as the beastmaster.
Have healpet commands consume TP instead of items this will allow them to interplay with dancer better

Bard:
For the most part I think bard is in a pretty good place all it could really use is some songs to emulate what Geos can do for the party (Magic attack and magic accuracy) most of the previous changes to jobs bard frequently subs will open up a lot of interesting options to them.
Ranger:
Let all ranger job abilities and traits also apply to thrown weapons, it would be nice if we could get rid of expendable ammo, you should still have ammo slot items ut just don’t make them expendable, ninja and RNG have to spend so much gil just to play the game before they get all their DREAM weapons. For stances, I would give them the following both accessible by subjob:
Barrage: Greatly increases ranged attack speed, gives a trait similar to double attack, or triple attack for ranged attacks at high levels (double attack at 49 triple attack at 99)(for TP move spamming)
Sharpshoot: ranged attack speed penalty but Large ranged Accuracy bonus and a bonus to Weapon skill damage(for closing skill chains)
Give them lvl 1 dual wield 1
Move Shadowbind to level 1 give it 100% accuracy like elemental seal, stymie etc.