I thing that you go with Mid-Nor problems too far
Making quite numerous army needs first 2-3 units to be cheap in all their Tiers - nothing more.
While Sparkling of Flash is indeed little OP but in packs up to 3 its acceptable - especialy while Swordsmans (T1 and T2, T3 is more usefull but have cost almost same as Valkyrie and can be torn apart by Guardians of Equilibrium much too fast in current meta) are still much more UP than flashes are OP
ign: Draconnor, Cynwall player, 23 years in computer games, 14 years in battle games, 8 years in Confrontation Universe, 4 years of making own battle games.