I think you shoul level Wil, if I remember correctly you don't really have Rath long enough to make good use of him.  That is just my opinion, someone may think differently.

Wil > Rebecca > Rath > Louise

My main point here is that Rath is highly mobile, and that seems important for HHM.

That sounds about right.  I've actually never understood the mounted archer idea.  Since I find most archers are sheilded by your tank units (knights ussually), they never really needed to mover further than them.  The more movement of Rath is ussually wasted because it puts them in to much danger.

Rath can have the best stats of all the archers and high movement but you get him relatively late in the game.  If you want to spend the time to level him up then you won't be disappointed.

If I'm not mistaken, Rath is the classic case of overpowered unit when you get him, but when he returns later he is to far behind to really be useful.  When you get him back later, Wil should easily be better then Rath stat-wise (minus movement).

I don't remember the specifics on when he comes/goes.  Only that he was a late joiner and suffered for it.

IMO, the real debate is always Wil and Rebecca which basically comes down to "Can Wil double the enemy?"  If the answer is yes, Wil is better.  If the answer is no, Rebecca is better.  Wil has great everything but speed while Rebecca has great speed.

In several of my playthroughs, Wil and Rebecca had abysmal growths. I just like using Louise.. ^_^

Boo prepromotes!

^^

I like prepromotes.. especially Karel. Karel >>> Guy.