generally if you want super comfy runs, you can do a setup like:
cleric support
cc mage
falconer
2x dps
This setup is able to clear stage 5 very easily, though of course depending on who you have, there are many other setups that can clear stage 5 effectively.
Generally for cleric healer supports, classes that are very good in singulartiy stage 5 are a combination of:
Paladin: very helpful and generally a good fail safe to help with buffing your party damage setup but also to absorb any boss wipe attacks if its an unlucky boss via devotion.
Diev: Quite important in cd reduction which can enable cc mages to keep elites and bosses perma cc locked.
Oracle: More to cast foretell and disable the CC tiles that the elites spawn nearby which might lead to a wipe.
Priest: Generic aoe heal and revive can help with accidental situations that may pop up.
Kabba: Einsof max hp isnt too bad - though generally not really needed. the cd reset for your party members are always helpful in taking down bosses though.
Pardoner: indulgentia heal is comfy and Discerning Evil debuff time extension helps keeps elites even more locked within your cc mage spells.
Miko: migo is cute and the party wide buffs are very comfy.
For cc wizards, generally you can use a combination of:
Pyromancer: firewall can keep elites away from your party, while firepillar can lock them down if they are standing underneath it.
Cryomancer: Frost Pillar does extremely well as a fast acting cc to freeze both bosses as well as elites over 10 seconds. Snowrolling is quite risky to use since elites spawn cc tiles which might petrify/scilence/stop you if you are too close to them, however if you have the proper timing and setup down then its good. Ice wall is able to freeze bosses as well as elites which is why its super comfy, but you’ll need to know how to position the wall as to not incur the wrath of dirty ataka users.
Psychokino: Gravity pole(non arts ver.) is extremely insane in pulling in elites as well as lowering their defenses while locking them down. This coupled with Magnetic Force that pulls enemies together can be very useful so your party doesnt get overwhelmed from multiple directions. Heavy Gravity and raise arts combo is good to stop mobs from moving and give your party some breathing room once your other spells are on cool down. PP is able to cc bosses as well but at a chance, use it only if you have literally everything else on cd.
Onmyoji: Not the best cc class with only tiger roar being super useful for short term cc and interrupting boss attacks, and also greenwood tree being a very smol succ. It does however make up for it in damage synergy but i will leave that out of the equation in terms of cc wiz.
Elementalist: Hail is quite useful as its able to freeze bosses as well.
Terramancer: Horn of Golem circle CC is pretty nice in grouping mobs together.
The reason for falconer is actually to help your cc wizards land their spells on as many targets as possible over a wide radius. Without a falconer, runs tend to be much harder as bosses or elites that spawn in multiple directions can sometimes not be cc locked. Falconers pheasent spawmming are also very useful to knock the elites down too and is really comfy for stage 5 singularity.
You can couple falconer with classes like mergen/arba/cannon for dpsing as well as appraiser to help with your party dps.
Your dpsers in the party can literally be anything that does good dps. Any base class tree will do. Things like bbs/sorcs/etc.
Remember, depending on who you have, you can alter the setup as neccesary.
Some runs are able to be done without a cleric support, substituting it for another cc wiz or heavy dps.
etcetcetc.