Could you share a little more background about why you're engaged in this project?

Biologists are elated that Darwin figured out the core of the idea needed to explain diversification, but nobody pays attention to exactly what he said any longer. Hardly anyone even knows exactly what he said. Everyone is standing on the shoulders of Darwin and Mendel and Watson+Crick+Franklin+Wilkins and Morgan and Haldane and Hardy+Weinberg and Wright and so on and so forth, not just Darwin. So it's not clear where you could go with this biologically.

For instance, the most common mathematical formulation of selection has fitness, w, as (roughly) the expected fractional representation in the whole population of one's own offspring who have made it to reproductive age. You can do it however you want. Nobody's like, "Oh, Malthusian resource limitation doesn't apply here so never mind about fitness". The math doesn't care; just put in the bottom line and it applies. Expanding population? Fine! Shrinking one? Whatever!

Incidentally, this points out why regulation island is a difficult to achieve: what affects future allele frequencies is differential reproductive success, and rabbits whose genetics make them feel like having more offspring will--unless stopped by the other rabbits or some other mechanism--gradually take over the island. If you can have islands compete, then the cooperative growth-limiting rabbits win. If you have rabbits compete, the too-many-progeny ones win, all else being equal.

Furthermore, the exact formulation of "selection" that you critique isn't used to decide whether something "is" or "is not" evolution, so it's not clear where you could go with this in a more ontological bent of considering what "evolution" "is" fundamentally.