I'd rather cross server with same level range (1-19 20-39 40-50) than have a full warzone with so much level difference. It makes the game so bad and unskilled.
The big main difference is skillsets.
We know the ability is bolstered, but a lvl 20 cannot have all the new skills a lvl 40 or 50 has. That's unequal and careless.
They just went the easy way to make up for population loss.
Another big difference is equip. Lvl 50 may have purple pvp gear giving them dominance or whatever the pvp stat is called, plus having more stats overall, even bolstered.
So yeah, big mistake for bioware on keeping this kind of system in warzones. I really hope they reconsider it and modify/delete it.