1. For rubber, "shave" the tree. Leave the top leaves, and cut the rest. Also leave all the logs, and tap it once. You'll get saplings and get a good farm going.
2. Other benefits are GREAT, solar power is a quick and rather simple way, you pay the cost for convinence. Geothermal, reactors, redpower watermills, etc are well worth it later on. Reactors can produce 2000 EU, PER TICK. This would require 2000 solar panels, and it'll work only in the night. Or, the less high ones can do 100 EU/T,100 solar panels and only really require uranium to continue running. Solar panels are basic, and shouldnt be used as your main power source. Switch to soemthing else ASAP.
3. The IC2 autominer isnt worth it, buildcraft quarries are also pretty fast, but you need a lot of power for them to go.
For above, dont use water buckets for internal cooling, either use cooling cells or intergated heat dispersers, or if you can, ice.