Even though im not part of the development team, i think i can clear up some of those questions you asked
The stats affect the life forms (seedlings, mines, flowers) a little differently, I'll try to summarize and clarify what Rudolf described above:
- Speed is obviously influencing the speed of all life forms.
- Energy determines the hit points of a life form, i.e. how much they can be attacked before they die. For seedlings, the more energy they have, the more damage they do to an asteroid core ("sapping power")
- Strength obviously only affects seedlings and mines, whose attack value they determine. For laser mines, the more strength they have, the more damage they do in the explosion when they die.
So basically, you can create kamikaze-laser-mines by growing them on an asteroid with lots of strength but very low energy
Asteroid population is (default-)set as a map-setting (Globals.Asteroids.SeedlingCap and Globals.Asteroids.SpawnCap; the latter determines when Dyson trees stop producing), but apparently can be changed for single asteroids as well (refer to the scripting reference for this; once in the global vars section and once in the field section for asteroids)
And yes, you CAN read out the current and maximum energy (hit points) of any entity via Lua (refer to reference for this as well, section "General game entities"). Im not sure if Eufloria allows the scripter to create additional UI overlays -- if it does, you could show the hit points that way. Any "visual queue" like for the trees would probably require change to the game code though (i.e. patch).
And the regeneration rate for trees is determined by the global variables Globals.Structures.RegenRate (Dyson trees) and Globals.StructuresDefense.RegenRate (Defense trees)
Hope this helped a little ^^
Regarding heredity, im affraid i dont know, thats a question for the developers to answer
But im also interested in that, mostly in how a flower influences enhanced trees and super seedlings (if at all).