20 is not “a few”. 20 is a lot. And for that matter, we already have 35 civs and the game is already really hard to balance right now: even 5 more civs would make this more complicated.
Furthermore, all the effort for new civs and concept is probably going into aoe4. the game is perfectly fine with 35 civs, they should just add the possibility to create new civs with mods so that they can be used in SP or in the mod
Realms mod is really bad and more than half of his civs are really really bad designed. Let me bring some examples to the table:
Armenians: their kts get +1 pierce armor in castle. This is already busted. Their UU has 210 hp, 15+5 attack, 2+4 melee armor and 5+5 pierce armor? Does this look balanced to you?
Tufans: they get cavalier in castle age. Seriously, I don’t know why someone thinked this was a good idea.
Those are just a couple of examples: it’s hard to make new bonuses that:
Actually, I think that true competitive players should enjoy to be outside of their comfort zones which means welcoming new civs, having to memorize a lot and play other maps than pure land maps.
I never understood this obsession with the most generic land map which is Arabia.
Honestly it is hard to say what is the limit of civs the game balance can handle. We have been pushing new bounderies ever since the Forgotten expansion while at the same time we do have now the best balance we ever had. But to do that we have had active game/balance support since HD and there are still few things to be improved. Adding only a couple of new civs affects all of the rest at least in some way so it needs fine tuning at least several patches.
Having said that despite since AoC some ppl were saying we already have more than enough civs. I have to say FE have done fantastic job designing new civs balancing them and giving them idenity. But where is the limit really.
Several times new expansions/civs have made design decisions that changed our perspective of what is possible. Starting from AoC Huns not needing houses felt revolutionary. Also having Meso covs with no stables and having eagles was completely different from what we had in the original game. Later we saw units take half pop space when one of the specifics of AoE2 always was any unit even a siege, a ship or an elephant raider takes 1 pop space). Most recently we are having Khmer farm bonus, lithuania relic bonus, Cuman feudal TC option, a unit that generates gold when fighting. We now know civs can not only have unique units and techs but buildings, too. ( Feitoria, Krepost).
When we factor all those out of the box ideas already implemented we realise there is possibility for few more (5 may be maximum 10 more civs). More than that the game balance and civ design will just implode with too many, too crazy ideas. And mind you most of those listed above were already considered game breaking at some point.
Because most of these topics in all forums usually say what civs should be added I have been thinking about a civ design without particular civ in mind perhaps some African civ.
Hunt resources last % longer and do not decay
military units cost % less food
can Fortify Town Centers
Do not build Castles
Trebuchet, Petards trained at the SIge Workshop
UU (shirmisher like unit a little stronger). Produced in the Archery range from Feudal Age, good against archers but also against camel and elephant units.
UT. Fortification ( researched in every TC separatelly cost X stone Y gold) TC gets more HP, range attach (changes visually) and gains access to Castle techs (weaker than a Castle stats similar to Krepost)
UT. ??? I am thinking some camel & Elephant related bonus + spd or armour
Team Bonus. Town Centers research techs % faster
The civ would have access to Batte elphants. This would be a fairly crazy idea of civ design. but could be unique and interesting if balanced well
The Persians still have the Middle Eastern set because they’re primarily based on the Sassanids, not so much the later, Muslim dynasties who used the Central Asian architecture. Sassanid architecture was much closer to the brownish Middle Eastern architecture set than the colorful Central Asian set.