Now generally, i got (Grandpop's Pusher) but with a few modifications.

Level 1 (great!)
Level 4 (Prolific Dispersal) both lowers cooldown, and increases charge. Often times my teams mates are absolute noobs and i end up having to defend an objective by myself. The mines are the only way i can delay enemy team by myself. Ballisto is pretty good too tho.
Level 7 (Needlespine) allows me to contribute meaningfully to team fight without having to build for it.
Level 10 (Evelution) Now. Every game i've played with monstrosity i've lost. Why? Beacause i cna't contribute to team fights. While often i do the locust build for pushing i still need to help team in teamfights.
Level 13-20 (Great!!!!)

that's my simple build