Lapa, I am by no means an expert in the LA 5 (or anything else, for that matter) but I fly it a lot. I have a love/hate relationship with the thing too: I love to fly it but hate trying to get kills in it. A few thoughts:
1. I don't think it's a great turnfighter when compared to Spits, Nikis, or anything other than the pure BnZ machines like Jugs. It's best fought in the vertical. It dives EXTREMELY well.
2. I haven't noticed any weird stalls or any other unusual flight characteristics, so I can't really comment on that. It will, however, snap nastily if you try to maeuver it too hard at low speed. When you find yourself getting slow, use the great acceleration to extend and grab- it climbs like a rocket at low alt.
3. The biggest problem is getting kills; aiming is peculiar in the LA5 because of the ballistics on the ShVak cannon (lots of drop) and the very large engine cowling. You may want to readjust your head position in the LA5 as compared to other rides; I have it set so the sight crosshairs are very low, just above the engine cowling. I found that when I had my head position set to what would be "normal" for other planes the cannons would consistently shoot under the target (beware you don't block out your trim indicators when setting seat position, however; they are inconveniently placed in the LA5).
You may also want to check your convergence setting every time you go up; it seems to have a way of mysteriously changing on the LA5 (checked it once and found that it had shrunk to 50).
3. Needless to say, with the aiming problem and the ballistics, snapshots are extremely tough and you have to get in VERY close for a tracking shot. This is very tough to do in the MA, where either other friendlies will snake your hard earned kill while you're trying to saddle up or the enemy will drag you back to those hordes of bad guys you mentioned. I get most of my kills in LA5s while "rescuing" friendlies who have a target obsessed bandit on their 6, usually on the deck. The plane's excellent vertical maneuverablity, low level speed and acceleration will get you into position and the bandit's target fixation will let you saddle up.
4. While tough to get kills in, it's also VERY easy to survive in; the only non-perk planes I really fear in the LA5 are an LA7 or a well flown yak 9u (unfortunately, pilots who fly yaks usually tend to fly them very well). I've heard that the LA5 is supposed to turn slightly better than an LA7 but I've never been able to manage that in a low and slow turnfight.
Hope this helps a little. Given that you're a Rook, I will also try to kill you in the kindest, gentlest fashion possible.