I propose we change from the "waves" system into a lives system (probably could work for skirmish too, but I don't really play that)
The current waves system is very unpredictable and can be a deciding factor in games.
For instance, the most common situation in push is at the beginning of a game, players with ssds load in faster and spawn, and those who have slower computers can easily miss the first respawn, but be there for first ten seconds of the game. Now they respawn after 30 seconds-ish, while the first wave is just nearing first contact. Late spawners spawn, first contact takes losses, and trigger the timer for the next respawn wave (given some unfortunate timings). Boom, under the worst circumstances, theres 3 waves gone within the first 2 minutes of the game and a scattered offensive/defensive (2 waves - 12-13 waves within 1-2 minutes)
Another fault is that waves can often punish players who do well or those who don't die with the majority. Since spawns trigger and count down from ~30, surviving another 30-40 seconds aftering trying to hold the line leaves those players waiting for another respawn trigger as well as missing out on a potential life to do more damage.
Now the lives system I propose won't deviate from too much from the waves system. I simply think that instead of 15 waves in the beginning of the match, we start with some finite number of lives the team shares (adjust numbers based on data). The team still spawns in waves, but depending on how many players die subtracts from the number of lives, leading to a more consistent number of attackers to attack. In case of having less lives than dead players, the final respawn wave should act as it should now, respawning all dead players for a final push. Another added benefit is that this change would definitely reduce the amount of fast stompy games and allow a team to switch tactics more fluidly.
TL;DR: Waves suck because they aren't consistent, where it can sometimes spawn 5 people and sometimes a whole team, depending on the situation. Lives in waves would alleviate the problem, and missing a wave would be less detrimental to both teams, but especially the attacking team.
Also @NWI, please hotfix the bug where you get skipped over for respawning in push. Actually the worst thing about this game for me.