I am in bronze 1x1 (hope to switch into Silver soon) and 2x2, Silver in 3x3.
But usually I don't queuing units. Usually I don't have more than 3-5 hundreds of minerals free, 2-3 hundreds of gas. Usually I order units: 2 per each production unit with reactor, 1 - in each other (1 - in each if I play Protoss, almost didn't play with Zerg)...
If I ordered all available production buildings (with 1/2 units) - and there are still a lot of money - I build new production building (according to my current build order and strategy).
If you make expand - you need to add 50% of production buildings.
Some time, I detect that I have more than 1k minerals or gas - in this case I very often lost games...
You right, if you are queuing - you are putting money on hold. Put them in new building better and next time you will order more units that will go to war right now.
Probably, it would be good idea to stack units before the big battle... but as far as I see from replays, good players have battles CONSTANTLY.
So my suggestion: improve your micro (my is still to poor in order just to mention it).