Yes, the default EU->MJ ratio is 1:50. It's pretty silly. I also definitely need to tune the energy costs, as mentioned. What would you think is a reasonable cost?
I'm also thinking of making it an exponential scale rather than a linear scale; so that, say, 200% sprint boost will cost 10x as much energy as a 100% sprint boost, and 300% will cost 10x as much as that, rather than costing twice as much.
Alternatively, I'm definitely going to change it so that rather than having a 'battery size' slider, you can simply install more than one capacitor in an item. Maybe this sort of discrete 'more upgrades = more power' would be more intuitive for people.
Was something about power conversions changed recently?
Your site states that it should be 1:1 unless UE is instlled, and i think it actually worked that way a few versions ago and seemed pretty reasonable.
Now it's using the 50:1 ratio which makes on one side everything ridiculously cheap in terms of power and on the other stock IC2 tools just murder my capacitor.
I'm not sure an exponential scale is a good idea, it's harder to understand and harder to balance (without making the low end stuff way too cheap or high end stuff cost way too much power).