Quick 'n' dirty rule of thumb for stock: You will spend the first 1,500 m/sec in vertical boost. This phase needs 1.7:1 t/w ratio. You should burnout right around 7km altitude. The next transstage 1,500 m/sec phase will get you to roughly 45* pitch. T/W should be 1.4:1. You should burnout around 25km altitude. The last 1,500 m/sec is insertion. 1.2 t/w will be fine, and it can taper back to less than 1:1 as you tip prograde. I don't necessarily use a single stage for each phase, and may occasionally have a stage bridge these phases (or even one stage do all 3). Best, -Slashy