Relying on “seasonal events” to balance out a poorly designed system is terrible design philosophy. What happens if my schedule is busy during the seasonal events and I can’t devote enough playtime to make it worth the while? If my playtime is worth X during every other phase, but during a limited window it’s worth 4X, but I don’t get to play during that quadruple experience window, then that window isn’t helping me at all.
A proper progression system doesn’t rely on time gated bonuses to balance out defeciencies. It should be balanced no matter when I log in to play.