Hmmmmm. I haven't noticed white tigermen to be too incredibly overpowered in the original FD mod, which i have been playing alot lately. They sometimes seem to siege more often, and in greater numbers, including mounts, but other than that... From memory i don't think they always use 2handed weapons in the original FD. So yeah, it sounds like the 2handed effectiveness is probably the issue.
Okay so i just read through your mod thread. Here's some feedback for you (or should i post this in the mod thread?):
Introduction sounds very good, my kind of mod. Elves playable, hmmm, something i've thought about but it seemed unrealistic and imbalanced. Can spawn more wood at altar... so much for staying true to the vanilla spirit?
The more dangerous wildlife stuff sounds good, as long as those extra syndromes aren't too strong. Equipment overhaul sounds like you've changed too much. I'm not sure a 2h > 1h/s > ranged > 2h balance system was necessary. Economy changes start good, but there's alot of things i don't like. Yes, it's currently too easy to have plenty of surplus of everything, and trading is generally pointless after the first couple of times, so changes in that area sound good, but i feel like you might have gone overboard. Mouldy stones?! Not very vanilla.
Smelting changes are strange. Removal of adamantine is fine, but i don't like the sound of all the new reactions, or the changes to steel making. Altar? Again, not very vanilla. Steamlined item types - i like dwarf fortress for it's huge array of different types of things, most of which are functionally identical - it feels more realistic. Bug fixes sound good, especially the clothing, and FPS tweaks, but some not so good - i don't like the removal of miasma or trampling.
Basically, "A mod designed to increase FPS and difficulty of DF while staying as true to the spirit of vanilla DF as possible" sounds like exactly the kind of mod i want, but the detailed description doesn't. Bear in mind of course that this is just my personal opinion
That all said, my current fort may end soon - if i'm bored enough, i'll give your challenge a go. Sounds like alot of learning the features of the mod though, won't be surprised if i die to something silly like starvation instead of the tigermen