The ruleset is ok but as you said, it exaggerates some problems that are much worse than the minor ones it fixes. Logistically it just isn't possible for lan or playoffs or regular season since matches can go infinitely long. People have stuff to do and you can't expect someone to stay up till midnight when they need to be up at 6am. There has to be an ending either caused by increasing difficulty or time. The only competitive games i know that keep going infinite are poker, chess and mobas and afaik all get increasingly more difficult for players over time until one who accrued an advantage earlier in the match comes out on top. Poker has increased antes depending on number of hands played, chess has reduced time gained per move after certain move numbers and the environmental enemies in mobas gets stronger and stronger until they end the game themselves.
In order to fix unity ruleset you would need something like this to force a game to end. Longer spawn times every 5 minutes that pass, or faster capture times, or a hard time limit. Then you have to think which one works, and which one do players want. These are the most important thing to think of when designing rulesets in this game since it isn't a high end competitive sport. You don't need to worry about which one is the most competitive since if it's no fun to play noone will play it since there is no other incentive other than fun.
It's why it's so difficult to have a unified ruleset when some people are playing for money and some aren't. Some things that would be tolerated if you were getting paid to do them wouldn't be tolerated if you did not have this incentive. I would not stay up all night for the chance to win 20 euros, but if I was in NA, and I had already invested the money into a whole season for a chance to win 300 dollars, I likely would. That being said, if I was in NA I wouldn't have started playing because of a paywall for entry. I don't really care how small it is, I just wouldn't have when I was younger and I had no money.
5 min round timer seemed fine, disagree that it didn't make much of a difference, it definitely affected strategy as teams would only push out of last if they could cap mid off of it. This didn't slow down the game since the round would just reset anyway if the team didn't push. Alternatively, could also go ape mode and just remove sniper, spy, engy, pyro and banners, That would be great to speed up the game. Allowing free entry for soldier sacs and medics nowhere to hide would do wonders. Could also remove golden caps during main season and have draws. Nothing wrong with that either so games actually end when they should.