The one big change I'd be in favor of is moving the offside parameters. Instead of it being offside for any legal ball-playing part of your body to be beyond the last defender, I'd rather it be that you're onside as long as there's any part of you that's level or behind the last defender. If every part of you except your right foot is behind the last defender, you're onside. If you're familiar with American football, it's kinda like how the QB can still legally throw a forward pass from beyond the line of scrimmage as long as any part of them is still behind the LoS when they release the ball.
I don't really have a problem with time wasting. Is there an actual rule against it that I'm not aware of? To draw from American football again, there is active strategy in letting the clock run with nothing happening while it is. Time wasting in situations like the GK taking too long to put the ball back in play are already legislated rules, maybe not always enforced as they should be but yellows do get shown for that. But if you're trying to burn the lock, and you're restarting after a dead ball situation, and you take the maximum amount of time you're allowed before you put the ball back in play...that's just strategy. You don't have to like it but there's nothing I see wrong with it. Please correct me if I'm wrong, but added time at the end of the halves is only meant to account for stoppages due to goals, substitutions, or injuries. Nothing else.
(I can take or leave whether corner kicks that happen after stoppage time has "expired" should be allowed. I don't mind the idea of a fluid clock and letting things play to a natural conclusion rather than the hard clock nature that exists in football, basketball, and hockey, but, once again, putting the ball out for a corner is a perfectly legal thing to do, so if the defending team does it and the referee blows time instead of allowing the corner to take place, then I don't see any problem with that. I guess the obvious problem is that this leaves this kind of thing entirely subjective to each referee and, thus, leaves no consistency in general.)