First I have to say, I love the spawn points idea, i hope to see it flushed out.
Now to business.... This may have been mentioned, discussed, and shot down already... but what about having the spawn points function with a timer?
for Example... Team A has a Pyra (P) and Galleon (G). Team B has a Junker (J) and a Squid (S).
Brawl begins. J is downed by Team A, he now has a choice of where to spawn. He decides to spawn as close to the battle as possible, meaning for 1 min that spawn point cannot be used by either team. Upon returning Team B kills P, who now has to spawn farther away, but Team A follows by killing S.
Heres the dynamic, now J and G are left alone duking it out, and both Teams have to decide if they are going to regroup somewhere else, or if they are going to try to hold for the calvary.
I could see it dealing with the meat grinder that happens more in most matches.