Laguz units require roughly 50% more experience to gain a level than their Beorc counterpart of the same level.

Are you sure about that? If you look at the BEXP, it's not that way with that. It seems somewhat odd that it is harder with regular exp, but not with BEXP.

Actually, BEXP is what I was looking at.

For Beorc it's:  (50 x level) + 50.

For Laguz it's:  (50 x level x 1.5) + 50.

It's important to note that Laguz and Beorc still max out with roughly the same amount of BEXP since Laguz only have 40 levels....

My biggest problem I have with most of the laguz is there growth rates. Most level ups outside of BEXP result in only 1 or 2 stats increasing, and for any character this usually a bad sign (this is almost always HP and luck). Looking at the level up percentages, the only laguz that have good growth rates are Januf and Ulki (its too bad they suck compared to Naesella and Tibarn). Looking at the lists, most of the tiger laguz will not level their strength enough to make a big difference.

My other complaint with the non-royal laguz is there weapon, it takes forever to get them to level up their strikes skill level, but even when you get their skill level to SS (which is nearly impossible because most good laguz OHKO), their strike is still worse than the Great variant of the same attack.

Also agreeing with Khuutra, laguz max out at level 40, this means there are 20 level ups that they are missing (potential stat growth chances). Now this even agrees with my first point, where most of the laguz have worse stat growths than several beorc, so the stat discrepancy of the lower leveled laguz really shines through if you take the time to level them up. The only way around this is by using BEXP, but that generally will cause characters weak in speed, attack, defense (depending how BEXP level ups go).

Volug's stat growths are actually really good, too. I think he gets like 3.8 per level up on average.

Most of the laguz have the illusion of great stat growths, they almost always get 2-3 per level.  Its a shame they never max out one of these stats so their overal stat growth is poor.  Volug will generally always level HP, speed and luck.  Looking at his other stat growth rates, I find it hard he would be consistently more than that (only reasonable ones are skill and strength).

Even this doesn't get around the fact that for laguz level up less, so they are truely handicapped by 1 bad level up.

Granted, but each of their important +1s (except HP) are effectively +2s, so I think it balances all right. If you take the time to raise Volug, he's very usable - arguably better than many beorc.

He certianly will be, but it when it comes down to Miciah's level's, is it really worth gimping ~2 other character to ensure Volug is at a useable level come Part 4?

There's actually a strategy for raising Volug in Chapter 3, in the level with all the enemy laguz... involves giving him Beastfoe and a good evade support, then leaving him sitting there in human form so he whips the Hell out of the incoming laguz. Appaently he can gain an absurd number of levels in very, very few fights that way.