I'll keep it short
1. Upgrade slots for IF, particularly for Ejector and Transformer upgrades
2. Constant heating option for both, thus not needing external redstone. Reason: multiple situations (can be seen in Direwolf's videos) with lack of block sides. Might be implemented as another upgrade.
What about some cables (insulated), infused with redstone, for conducting redstone signal? This would allow us to supply power to, and control, all induction furnaces with a single switch, rather than a manual startup/shutdown of each.
they shoud work as latch\switch:
recieving redstone signal toggle state, this will allow to on-off by redstone signal (without keeping signal source all time).
also gui switch shoud be here, but not as one and only method.