Some new plants:
- Chruberry. Tier 9. Special growth condition: Must have light level 5 - 10, and its dirt block is above a Block of Redstone. Drops three possible chruberries that have the same ID:Meta but are different because of NBT. One is dropped 90% of the time and centrifuges into 2 Tiny Piles of Redstone Dust. Another is dropped 8% of the time and centrifuges into Ruby Dust. The last is dropped 2% of the time and electrolyzes into Chrome Dust. Chruberry when eaten gives Wither for 2 seconds but has 4 saturation and heals 2 hunger bars. Its crop also can give out variable signal strength using a Comparator, depending on its stage of growth.
- Osmioplant. Tier 9. Special growth condition: Must have a block of water below its dirt block which is consumed randomly. 94% of the time drops 1 - 2 Hydroflower(s). Hydroflower can be used as a replacement for Water Cells. It can also be used in a Liquid Transposer to give 1200 mB. 6% of the time it drops Tiny Pile of Osmium Dust.
- BiuuMatter. Tier 10. Special growth condition: Must have an AESU with >10 million EU below its dirt block and randomly consumes 10 million EU from the AESU. 90% of the time it drops Scrapbox and 10% of the time it drops a piece of UU-matter. Players within 5 blocks distance may get Slowness II, Poison II, Hunger II and Haste.
- Quartzose. Tier 7. Special growth condition: Must have Sand within 5 blocks. May drop 2 - 3 Quartzose and 0 - 1 rose. 6 Quartzose + 1 Empty Cell centrifuges into 1 Nether Quartz, 2 Certus Quartz Dust, 2 Sand and 1 Methane Cell. 5 Quartzose + 9 Empty Cell electrolyzes into 3 Silicon Cells and 6 Compressed Air Cells.
- Electra. Tier 10. Drops 81% of the time 3 - 4 Single-Use Battery, 27% of the time 2 - 3 Full RE-Battery, 9% of the time 1 - 2 Full Lithium Battery and 3% of the time 0 - 1 Full Lapotron Crystal.
- Powder Plant. (Pun intended). Tier 8. Special growth condition: There must be 1 Creeper nearby. May drop 3 - 5 Redstone, 1 - 2 Glowstone Dust and 0 - 2 Gunpowder.
Well, most of these suggestions are OP, not going with the current mind of Agriculture or having conditions that you can't realize (really, must be one creeper nearby ? ...)
I mean, the IC² Agriculture is supposed to be a way to get easily stuff like Iron, and it's fun researching these kind of plants but ... the aim is not to provide you another way to progress in the game than using Machines part of the Tech Tree!
At least I agree an other kind of energy plant would be fun (because currently the only one give Oil and is a bit high level, a lower tier giving lower stuff would be cool to me)