They shouldn't make it more than 150....
Only because if a marine costs 2 food, zealot 3 or the others 3-4 that will be fine. Still many units, no need to mass. I've seen few SC solo games but I know they don't mass so much like 200/200.
I personally think 150 will be also mass but if they give them higher food cost it will be ok. I know SC is with more limit and is more realistic but come on, let's not make massing the way to play the game. I'm hoping not to see more than 70 limit in non newb games with only 2 players.