If they're more random there will be more possibilities for unbalanced spawns. I say make only 1 or 2 sets of balanced starting spawns. What's the problem in having a predefined strat? It's not like the first 2 minutes will be set pieces, people will quickly start going for variations to catch enemy off guard.
Because it will. People will soon figure out what's the best theorical play, what's the best theorical play to abuse it and shit like that. It's called a metagame and if something works, be sure to see people abusing the hell out of it until 2 months later someone manages to pull out some crazy shit that fucks the timing of an item by 2 seconds and allows him to get the advantage,,, it then becomes the standard play and it goes on and on and on.
And aren't 75% of current starting spawns set pieces already? Don't people delay items to throw off an enemy who knows the spawns already? The only problem is that the other 25% of the spawns are imbalanced and turn the game into a shitfest.