Radiant Dawn's four Laguz Lords, Caineghis the Lion King, Tibarn the Hawk King, Naesala the Raven King, and Nailah the Wolf Queen, are extremely powerful characters who deserve special mention. They are Laguz, but because they are so overwhelmingly powerful and do not operate under the same limitations that normal Laguz must suffer through, it is almost unfair to try to compare them directly. Even powerful third tier Beorc characters, who normally are so much more reliable than Laguz, pale in comparison to the mighty Laguz Lords.
The Laguz Lords have many advantages over normal Laguz. They all start at high level, have incredibly good starting stats, and even their stat caps tend to be higher than those of normal Laguz. For example, Caineghis starts at level 36 (four levels short of max level for Laguz), and his stats start out about as high as Skirmir can hope to attain, and a few of his stats (like Speed), start at what would be Skrimir's cap and can go higher still. What is more, most Laguz Lords start with SS-rank innate weapons (which are very difficult to attain for most Laguz), and their weapons are slightly more powerful than normal Laguz's innate weapons (Tibarn's SS Great Talon has 2 more Might and 10 more Hit than any other Hawk's SS Talon). Further, most Laguz Lords have a greater number of innate skills than normal, and far greater skill capacity. Finally, their greatest and most defining advantage is that they have the Formshift skill, which lets them transform at any time and stay transformed indefinitely without any regard for the transformation gauge that restricts every other Laguz. With all things considered, the raw power of the Laguz Lords completely surpass every other Laguz and all but the very strongest Beorc, making them unquestionably the strongest characters in the game.
The existence of these four extremely powerful characters severely distorts the choice of "who will I bring into the final chapter". Any character who specializes in melee physical attacks will ultimately be compared to the Laguz Lords, especially any Laguz. After all, the Laguz Lords can easily tear apart just about anything in the game other than the two strongest final enemies (one of whom is himself the lord of the strongest Laguz type, Dragon King Dheginsea, and the other of which is the final boss), and those two bossess are so powerful that the overwhelming power of the Laguz Lords is practically a necessity. There is almost no way to justify bringing any Laguz other than the Laguz Lords unless you either really like Laguz characters and just want to bring more than the Lords and the required Heron and Dragons, or you are deliberately holding back on bringing some of the Lords because you want to make the final battles a bit more difficult. Truthfully, it is hard enough trying to justify using a normal Laguz even without the all-powerful Laguz lords showing up in the very end.
I will say, though, that I appreciate the presence of the Laguz Lords in the earlier missions of Part 4 of the game. In the Fire Emblem games, it is often extremely useful to have a character who is reliably powerful enough to defeat any foe or hold any position. and having a Laguz Lord along with each of the three groups helped balance them out and let them survive some of the tough battles.
I also think that it was fairly appropriate that such power was given to the laguz royalty, characters who were given an incredibly important story role. Looking at some other data, there is some similar power given to some other characters important to the plot, such as Ike, Micaiah, Elincia, and Sanaki, who all have somewhat higher stat caps than comparable normal characters, though unlike the Laguz Lords their power is not as obvious and guaranteed (and they don't have either the boosted skill capacity or stats that can go above 40). In this regard, the Laguz Lords work very well as characters who are particularly powerful due to their role in the plot (which is usually associated with being royalty). That said, the immense power of Formshift throws things a bit out of balance. In many respects, the limitation of the transformation gauge is what keeps Laguz (whose stats can surpass 40) from surpassing Beorc (whose stats have an absolute limit of 40). As I described in my last post, the transformation gauge overcompensates a bit too much and ends up overly limiting many Laguz compared to Beorc, but because the Lords do not use the transformation gauge at all, they don't have any effect that reins in their power and end up being too powerful. As a result, while powerful Beorc royalty do not completely make normal Beorc characters obsolete despite their greater potential, Laguz Lords do make normal Laguz obsolete.
At this point, I wonder if it would have been better if the Laguz Lords simply had a more favorable version of their own tribe's transformation rates. For example, perhaps Caineghis could have had the high gauge growth rate of a Tiger or Cat, but kept the low decline rates of a Lion or maybe even a Dragon. That way, he would be a lot more flexible than the other Lions, but not absolutely better than them. Even just giving the Lords the ability to start each battle with a full gauge, rather than an empty one, might have been enough. There must be a way to make particularly powerful Laguz without removing the one trait that most defines Laguz as a whole.