iCake: Я летаю в Россию часто doesn't even remotely suggest that you will fly back from there
Ahh, yes, I see. I was confused because the past multidirectional Я летал в Россию (without a modifier such as
часто) normally does suggest a round-trip flight, doesn't it?

Yulia65: Usually this contrast ONE-TIME/IN PROGRESS vs. HABIT/REITERATION overlaps with one-direction vs. multi-directional contrast.
Thanks, that was very well explained and a good memory-refresher for me.