Questions on changing stuff for players ("trait-like" effects) on-the-fly through Lua

[Pazyryk]

I'm developing a trait system in my mod where civilizations gain traits based on their actions, dicoveries, surrounding geography, etc. I've mastered SavedGameDB so I have no problem making and keeping new "traits" for each civ (the traits being a whole new Lua/DB system unrelated to the core traits).

However, I'm trying to figure out the best way to change stuff for each player. By stuff I mean anything and everything. My only constraint is that it has to be changable on-the-fly (so "civilization" and official "trait" effects are not useful to me). Here are some ideas and questions:

First question: Could someone please list out all xml items and which ones work and which don't? ... Anyone? ... Well, darn. Didn't think that would get a response.

OK then. Policies seem to have the most wide range of effects. I can give and take these through Lua. Great. I can also hide them by jiggering display coordinates. (I don't give a darn about messing up cultural victory because there is no Utopia in my mod.)

1. Is there a way to get around the problem of increasing culture cost for subsequent policies? (Seems likely, given that free policies from various sources don't add cost.)
   
   
2. Do the Policy_FreePromotions and Policy_FreePromotionUnitCombats work as one would expect? It seems like this would be a good way to affect all units or a combat class at once, rather than writing Lua code to cycle through all units (trying to catch newly built and disembarked units, etc.).

Buildings. Lots of effects here. One possibility is to give a building to all cities of a particular civ, then cycle through all cities each turn making sure that all cities have that building (for newly founded or captured cities). Set NeverCapture=true. This works but is a pain.

1. Is there any easier way to give a building to all cities of a given civ? (Again, it has to be applied in game, so the civ free buildings won't work for me.) Has anyone tried to do this using the "FreeBuilding" tag (as opposed to the "FreeBuildingThisCity" tag)?

I'll have more questions but that's all for now.