Let's compare Humanist to Religious, one by one.
R: Deus Vult CB
Obviously, the CB is one of the best in the game, and often a must have while waiting for imperialism. Best for "lonely" religions like Orthodox or Shia, as most of your opponents will be a different faith.
H: 25% Religious Unity
The religious unity is quite nice, as you can avoid +stab cost and +unrest from disunity. Once you get rolling and have the religion you plan on keeping (post reformation at the latest usually) this becomes rather trivial, as you shouldn't have that much wrong religion land and you get this from other policies.
>I think this one goes to Religious. Unique ideas tend to win.
R: +1 Missionaries
A missionary, is quite wonderful. Double your conversion rate instantly. Once provinces get your religion, their unrest drops greatly.
H: -2 National Unrest
Getting -2 National Unrest is a great modifier, but it seems like a "band-aid" fix. You still are going to be converting the provinces to your religion (unless you humanist players leave you missionaries idle?) and -2 is not enough to avoid a revolt in a freshly conquered province of wrong religion and culture. Little utility here, if you ask me. Would help during westernizing, disasters, niche situations.
>Again, you can't get a Missionary anywhere else, save a few policies (which require religious...) and some triggered modifiers.
R: -25% Stab Cost
-25% stab cost is huge. When you stack it with national ideas and other modifiers, you can break the game. As Mamluks-Arabia, I was paying 2 to 8 adm points per stab boost under +1. This is an AMAZING relief from ADM burden over the course of a game (as a monarchy).
H: +3 Tolerance of Heretics
This is also huge. If your religion allows it, such as Confucianism or Buddhism, you can be on the path to ignoring any downsides of conquering wrong religion land. This can accelerate conquest greatly in that region of the world.
>This is a toss-up. The stab cost is great for monarchies all around the world, but some religions and NI's will see a greater benefit from the tolerance.
R: +3% Missionary Strength
This is one of the most powerful ideas anywhere in the game. You can now combine your extra missionary with this 3% boost to achieve and obscene conversion rate increase compared to those without religious. Best used with max Piety and Patriarch Authority to achieve trivial conversion times. If you snatch another missionary or more from Defender of the Faith and Triggered Modifiers, or your NI's, you reach the point where you don't care about wrong religion anymore either. Conquer, Convert, Core. Never see a revolt again. Less utility in the parts of the world that haven't gotten a DLC yet (east asia).
H: -10 Years of Nationalism
I don't get this one. I rarely see any revolts after the first one. The length of nationalism seems pretty trivial here. It can allow you to decrease autonomy and convert culture at an earlier time, but that doesn't mesh with humanist at all.
>Not really a contest here. Religious.
R: +1 Tolerance of the True Faith, +2 Yearly Papal Influence, +.25 Monthly Fervor
A must have for Catholics and Reformed, for obvious reasons. I rarely play Catholic and have NEVER played Reformed, so I'll leave that be. The Tolerance of the True Faith is great, and gives you even less revolt risk in provinces of your religion, which will be your religion even faster because of your previous ideas. Not the most powerful idea.
H: -50% Accepted Culture Threshold
Cool I guess. (So overrated) Anyway this helps you stay in one piece in the early game, but oops! Its 5 ideas into the tree, and by that time I assumed you've done quite a bit of conquering, especially outside of Western where it will take you a lot longer to tech up and reach this idea. The culture %'s will simply be too low to accept outside of ones like Lombard, which you probably could do for most of the game without this.
>The Religious one is only a must have for two religions, but the humanist idea seems quite trash tier unless you are Poland. Call it a draw.
R: +1 Yearly Prestige
Every tree has one like this. Its okay, and if you have collected some Romes and Meccas you can sit at 100 Prestige permanently, which is more valuable than ever in this patch.
H: +33% Better Relations Over Time
Coalitions are more abusable than ever, so I don't see why non-HRE players would fawn over this. Oh, its just HRE players.
>Giving it to Humanist here because that is a big bonus, but more because the religious one is weak.
R: +2 Missionary Strength vs Heretics
If you have a lot of Heretics to "deal" with, converting just keeps getting better. Helps Catholics survive the reformation, can be overkill to reformers who already get +8% from religious zeal. Can help east asians tear through the three blobs of religion going on over there. Vital for Shia/Ibadi. Can help Sunnis chew through the toughest conversion area in the game in Persia.
H: +3 Tolerance of Heathens
Cool if you already have some in your NI's or religion. Otherwise it won't really do much for you. At all.
>Since the argument is that Humanist is good for East Asians, I think conversion against heretics will do them even better. Convert high base tax china in a jiffy.
R: -25% Culture Conversion Cost
One of the least important aspects of the single player game, and more of a roleplaying game. But some people love it, and if you have a pile of DIP than its great to quickly and cheaply remove a smaller culture from your empire entirely and collect full tax from it. (your silly accepted culture threshold would have you leaving this there the whole game unaccepted)
H: -10% Idea Cost
I don't know what this is doing here, but it is quite nice. At the end of a tree no less. This solidifies Humanist as idea group that you must take first or not take at all. With better trees like Administrative, (and Religious) and situationally Expansion and Economic sitting there... I don't know how this makes it worth it. Probably good to combine with protestants-to-be.
>The Humanist idea here is better. I already explained why its not worth it, but in a 1 to 1 comparison it is better.
Humanist appears to be the poorer choice on average. It has some things that look great on paper, but you are not considering the opportunity cost. With new restrictions on idea groups, taking Humanist instead of Religious seems like an awful decision. And you pretty much have to take it first to get any utility out of it. Nations that get the best use out of it still seem better served to take Religious. For the few nations with NI's that can take advantage of some stacking (Poland... and Poland?), go ahead. There are actually so many more nations that can take advantage of stacking with Religious, the best being Byzantium (super overpowered mode) and Mamluks, Russians, Timurids, and any European start, Muslims, all of the New World, Africa, East Asia, Hordes...
Please argue my point substantively, I wish to learn more reasons why to take this group.