39 chain ring versus 30 for climb IS a big difference.

If you are finding it really hard, do switch to compact double and use 28 cog in rear. Not sure what cog set you have right now but I would suspect using a compact double with 28 cog would make it much easier.

Also, do remember that your top speed is going to be compromised because your top gear is going to be lower than using a "standard" sized chain rings 53/39 with 11/23 kind of cassette.

If you do decide to switch to a compact double, do remember that your front derailleur location on the seat tube must be readjusted.