I was about to go offline, but when I saw this intriguing sentence I couldn’t resist:
I think you’ve got the right idea for て! Unfortunately, if that’s what you wanted to say, the sentence is slightly off. Two things: 1. 戻る=come back (to a place); 帰る=to go/come home (and it really only works for this sense: going back to one’s home country, home province…). So it should have been 戻って 2. もう is closer to ‘already’, so it’s more like ‘oh, come on and do ~ already!’ Also, erm… I feel like もう would only work if you were talking to Zizka when he wasn’t on the old forum. It’s a bit like telling a family member, ‘Come home already!’ when they’re standing in front of you at home.
So, what your sentence actually translated to: ‘Please go home and write already!’ = ‘Hurry up and go home and write, please!’ Like you said though, yes, it’s possible that the person goes home in order to write.
For what you wanted to write, I think 早く戻って書いてくだい=‘quickly come back and write, please’ works, but I think 早く書きに戻ってください=‘quickly come back to write, please’ is better. It’s like when Japanese people see off some friends after a party or a nice chat over dinner. I think one thing they can say is また遊びに来てね！(literally ‘Come (by) to have fun again, ok?’) Speaking of which, you could replace 早く with また in the sentence I suggested, and add a ね at the end, but then the idea of ‘soon’ is only implied by the tone, and isn’t in the sentence itself.
Anyway, with that, I’l go offline. See you guys again.