Have you actually played PvP? The mods, ehp and weapon balance are completely different. The real problem is that ehp and mobility are not balancedand there are just too many weapons and warframes to balance. They tried starting from a clean slate in conclave 2.0, but the stream of content warframe gets is just too much for a 1-2 person team to properly balance in their spare time. Realistically speaking if PvP is ever going to be good, it needs a proper full time team, and that's not likely to happen.