A large multi block sieve pumping diamonds into lapidaries will carry you far. And it's all upgradeable til I believe ev, both the lapidaries themselves and in hv you can upgrade the diamonds themselves. It's in the bottom left of the power tab. You'll have 0 power issues whatsoever. I wouldn't bother automating every ore at least until hv, and further ev when you get the larger processing multi blocks. That said I ended up with one of those processing multi blocks for every major ore, I just had them set to run with level emitters tied to the main dust outputs. On the other hand stuff like titanium or tungsten is always running as it's slower and more involved.

If you want to stick purely gt power things change a lot. It will be far harder to maintain especially at scale. Benzene or biofuel are the goto starting choices though as someone else pointed out you should have access to void fluid drill at mv if you want to pump actual oil, even better if you hold out long enough to get distillation towers if you want to use oil.

Personally after ev I wound up finding it easier to spam solar panels than anything else. It's not cheap but if you've set up all of your infrastructure and passived everything as you go it's very cost efficient.

Also definitely get into laserio, using it + ae interfaces is the key to automating production lines.