It's hard to pick one account type from the presented. Both of them are good for my trading system.
The main advantage of Classic account from the ECN one is that it is not a commission-based account; and I don't need to pay premium for more competitive spreads.
But on the flip side ECN account has a much more superior execution type. Which in its turn entails tighter pricing and less slippage occurrences.

I also, can't say that $4.5 commission per whole lot is something very big. It's actually lower than the forex market average. I've seen much more substantial commissions per lot.
I think, it all comes down to the trading strategy you try to implement.