The conversion rate was quite high actually, and it needed a lot of string.
String was an absolute non-issue the moment you got your first flax seeds. The amount of it you got from a single 9x9 field harvest was just stupid.
The new Remain in Motion (Which is the 1.7 replacement to Redstone in Motion), now has an option to require power. Link.
RiM also had far less problems than RP2 frames while actually allowing people to, *gasp*, configure the options! That's one of the (many) options RP2 didn't have.
Actually it was not balanced, she did repeatedly say that the recipes were temporary until she got her multiblock machines built (of which they almost were done when she got overtaken by real life), they were going to become drastically more expensive at that point, and I do not mean in just creation cost, I mean in on-going cost. There was going to be more bluetricity usage. Solar and wind power were still very low tier, the new multiblock machines she created were going to require *multiple* concurrent wind generators going, or a higher tier power, which involved types of fuels. Green power in RP2 was the lowest tier power possible, you were going to be very polluting very quickly if you wanted to generate any useful amount of power at all.
Yes, I know her mod was "alpha" state but it was in that state for several years. At same pace we'll first get Minecraft 2 than non-alpha RP2. It doesn't really matter that she said "it's just temporary" when in reality that "temporary" stuff had existed for far longer time than vast majority of popular mods out there.