can anybody help me with this sentence?...

Hi,

I'm writing to an old friend in Japan who i've lost touch with a bit.
I want to say 'I hope we can write to each other'.
The best I've come up with is Watashi-tachi wa otagai ni kakikomu koto onegatte (sorry about the romanji, this computer doesnt have the right fonts).
The second half of the sentence doesn't sound right to me.

can anybody advise?

Many thanks!

My attempt

お互いに手紙を出し合えたらいいなと思っています。
Otagai ni tegami wo dashiaetara ii na to omotteimasu.