Early game should be balanced differently than endgame. In addition, it doesn't sound like you ran with a standard setup: a motley crew of SRs and Rs. These games are designed to have a low barrier to entry, then ramp up the difficulty over time to induce players to pay to overcome each hurdle they encounter. You used an exploit to overcome one of those hurdles--access to stronger characters with better stats and better skills--but presumably the early game is balanced assuming you DON'T do that. Elemental matching only pays dividends with investment. In early game, it's actually more effective just to switch up your team / main-hand weapon to counter the element of whatever enemy you're facing, especially if you don't have access to strong eidolon effects.
Also, Ultimate difficulty should be coming up in Event 3 (2 weeks). I doubt it will be trivial.