You are looking to minimize, change and/or remove 2 main areas (Garbage Time and Stalemates)
All of the possible "solutions" I saw in your #2 post hurt the natural flow of the game IMO. It is true that putting time constraints on teams will force them to engage more heavily because of the time pressure. It will truly only impact the attacking teams and does not address the inherent advantage of the defending team in every situation.
I feel the only way to break this is to shorten the respawn timer significantly, perhaps by 50% or more.
The main reason for a shorter respawn timer is to encourage more 6v6 style team fights on every point. This will mean more action and less incentive for both teams to play passively and not risk anything.
I realize this will probably be an unpopular suggestion but, unlike mostly all of you, I played in the era of instant respawns and can tell you hands down the action was non-stop, the game was more fun and the teamwork needed to be successful much more gratifying.
With a shorter respawn timer it will open up incredible possibilities for both attacking and defending:
- It will remove the idiotic "just live" mentality so prevalent/necessary in our game these days (this slows the flow of the game more than anything)
- There will be much more action and risk taking because of a quick respawn
- off-classing would happen much less (another huge problem that slows the game down)
- Stalemates will by more easily broken or countered (No more 1 player sac, rinse & repeat for 10 mins)
- Teams could sac 3 players at a time and still have a full 6 to engage in a 6v6 team fight after they respawn (more action, removes stalemates)
- Lot more examples but didn't want TLTR