Ele for the movement cripple?
I’m not sure what you mean by fastest. I’ll guess and assume you mean keystrokes and will not be in sPvP where reflexes and fast reactions times are everything. In that case, you need not worry about a bunker build. Bunkers are a PvP build for 1v1s and are not needed in Pve or even WvW if you run with a group. Because you will not be doing that, you have a wide range of build options. The sky is the limit. Level him up and have fun!
Don’t worry about being too slow.^^ You will get used to it and unless you are playing a lot of PvP it doesn’t really matter.
I would suggest you should create your own build to understand how the ele works. This might help:
https://forum-en.gw2archive.eu/forum/professions/elementalist/Guide-Rating-Elementalist-traits/first