that's fine and I"m not saying anyone "owes" us anything, but think about it this way: if it's anyone's task to balance it, it'd be the mod creators since they're the ones working with the code, etc. and they created tekkit
the amount of work is a non-argument since all that work will fall onto the server owners themselves, therefore creating fragmented tweaks and versions of so-called "tekkit", otherwise you have unbalanced pvp
Saying PvP is an afterthought is also moot since tekkit without PVP makes all the armor and weapons pretty much pointless, not to mention PVP has been around since before release. MC was released with PVP and PVP related potions and enchantment system. Anything before that was just in incomplete version of minecraft.