They’re very few and far between but they should get credit where credit is due. The one I can think of would be carrying carcasses. I think that would be a good addition to AoE3.
The one other thing AoE4 does better is walls. However, in the gunpowder era walls are much less important and most of the issues with them are specific to AoE3 (inconsistent cost of pillars, not being able to put gates on trade routes, etc). I don’t think guys on walls would really make sense but some bigger style walls like what is seen in the campaign could make sense for a few civs like China and Malta. Maybe they could have extra perks like absorbing some of the ranged damage from units firing through them.