create feature then people adapt... 

So, isn't the advantage of cavalry their high health? They cost extra due to their superior speed, but they also have a massive amount of extra health.

Is it? I can remember proper tunnels one could make only in Earth 2150, and an underground level in Heroes of Might and Magic… but then barely anything else, the Zerg tunnels in StarCraft, which I don’t think 0 A.D. should aim for (to avoid a teleporting effect).

I guess you didn't understand what I said in the first place, which was: no unit should be so OP as to have some gentlemen's agreement not to produce it, and when there's a misunderstanding regarding that, to have people whining about it, as it happened recently. So, if you say "champ cav is nonsensically fast", "naked fana has capture speed of a champ despite not having any of the drawbacks of a regular champ", and what you now added, I'd assume you agree with those complaining that they are OP, so I was agreeing that they should be nerfed, at least to the point of no ban needed to even be considered.

What's the point of more teams? When there are more then 4 teams at least one player is a lone in a team. So it has the same effect as to assign no team to that player.