Is a full heal/support cleric something that is really needed end game or am I torturing myself for no good reason?
What build are you thinking of?
Whether something is worth it or not is a value judgement only you can make.
To help us answer your question accurately define what “worth it” means to you personally.
It really does depend on your build. If you were to go something like Cleric 2 > Priest 3 > Chaplain > Plague Doctor, that’s a pretty standard build that’s reasonable to level up and provides a lot of support. But it also provides a decent amount of damage. Honestly, most “full supports” will do enough damage to get by, as long as your put your stat points into the right places.
What are the right places?
Depends on your build. I think Chaplain/Priest goes full SPR? If you were to do something like Cleric 3 > Diev 2 > Pardoner 2 > Plague Doctor, then I think that would be Int based. Different classes scale with different stats. It’s mostly a matter of making sure that you pick classes that scale off the same stat(s)/have good base values, and then you put your points into that/those stat(s).
Maybe stay on cleric 2 as a full support, no need to get 3, its a bit overkill. the previous mission i had was with a cleric 3 paladin 2, the heals were too much on the ground and later on he just used them to damage the boss instead, lol.
You don’t need to run full SPR to support as Chaplain. They are sub-DPS support class and mainly scaled off INT (90% of their skills)
Also, C2 Cleric is more than enough to support your whole team with mass tiles Heal.
Blessing and Sacrament scaled extremely bad late game because Blessing has flat based scaling and Sacrament is highly depending on Element attack to boost up the DPS
Plus, late game is heavily depending on Block, Evasion, Critical, Magic Amplication, Armor Reduction, Debuffs, and massive Heals.
A good example would be Earth Tower, I rarely seen Cleric with C1/2 Priest (Except for C3 Priest > C1 Chaplain), but still they all have C2 Cleric to support their team.