I would strongly advise for 50% or less throne points to win. Any more and you're effectively fighting for total map control.
I don't think it's that much in that way, in a "small" game.
Little example with the 4.03 game (6 players) :
There were 7 thrones level 1 and 4 points needed (half rounded up). I played Oceania, and won, while clearly being behind most of other nations in military power until 5 turns before the end of the game, and being at war with the most powerful nation.
Admittedly, I wouldn't have won with the current game version (because you now need to HOLD the thrones for one turn, as the throne claiming happens after battles, but I only lost 1 throne during the claiming turn, so with a 42% throne points needed, I would have won (or somebody else would have won, earlier in the game).
In a 12 players game, 60% throne points needed clearly means that the winning player would have won (90% of the time) a military victory a few years later, but in a 7 players game, I think that 50% of the throne points would be "easily" rushable by a triple-bless Mictlan or some early game power like that.
I think a 7 players 9 thrones (all level 1), 5 points needed could be a good thing, for a game that would force players to scout their neighbours (so you don't treat a throne-less nation the same way you treat a 3 throne one).
Oh, and about general throne number :
I think that 1.5 throne per player is a higher limit, not to give a big advantage to H3 capable nations.
And I also think that level 2 thrones are a bad idea (or that they should be in really limited number), as it quickly lower the number of thrones needed.
I read reports of a "blitz" (low throne number for a fast game) in the dom4mods game where I played (and was eliminated quickly), and the winner surprised most of the other players and said that he won because he was lucky enough to spawn near the 2 level 2 thrones of the game.
And about fast research :
We're used to normal research speed, and fast research will change the balance of the game, but I don't think it's wrong.
It can open possibilities to some nations (and of course reduce the possibilities of others).
I'd like to try it in a "pseudo-serious" game like the ones we have here.