IC2 challenging? Since when?
It's tedious, but not challenging.
I see it the other way. TE and dartcraft are simple, easy mods, with no challenge. IC2 gives you a challenge. But, each of us has his own idea of fun so as Antice said, offer configs to change things. Keep explosions by default, but let people turn them off if they want. In 5 months of daily playing, ive only blown up 3 items. 2 in the last few weeks! it added realism, IMO.
Its like playing peaceful mode, vs normal mode but basically 'peaceful' in that you have an MPS suit or whatever, and are not really in danger. Even with the best suits, there is some danger. The other day I forgot to torch the top of my base/tower, and a creeper spawned at the top. if I hadnt noticed it, it would/could have fallen/jumped to get me and id have lost some machines. Is it just tedious to rebuild the machines? To me it's that small fear that keeps things exciting. Flying up to check my fuel tank and seeing that creeper staring at me gave me a shock. Shock = excitement. Watching probably 100K worth of ingots explode and hoping all the ME disks survived = excitement.
Id still like to see bases of people who dislike ic2 and like TE ... 80% of my base is running off EU right now, with TE/BC id have one row of machines, and that would be it. Really, ALL of what we do is tedium. Why do you smelt dusts, why not just make one block that turns an ore into two ingots directly? Requiring two machines is just tedium, isnt it?
If the fun is making them work together, well then thats why I like extracting rubber to make copper wire to make circuits to make other machines that do other basically pointless things. IC2 is just ... MORE of what TE is, not different.