做項目經理最難的是處理與人的關係。上級下級都不容易。即使你一直這方麵都不錯,你也要意識到,你做經理後跟人的厲害關係不一樣了。另外以前你需要擺平的是工程師,相對容易。作項目經理後跟你搗亂的人的水平明顯見長, there will be difficult politics。會有很多headach. That said, if it is something you like to do, and feel rewarding, or you can't stand being engineer anymore, then go for it, like what Sigma said.
But, first thing comes first - first baby should be before you turn 35.