yes, there are some things that you can convey more accurately or precisely in lojban but... i think this is a poor example. Also, I think you're forgetting that translation is about intent not literal word / phrase conversion. The intent of "i'm talking with you." followed by something that indicates that the prior sentence takes place in the future translates very clearly into "i will be talking with you in the future" You can get all picky about verb tenses and say "oh english doesn't have that tense" but a) it's not true ("I am talking with you in the future.") and b) it ignores the point of communication. To communicate concepts between entities. The concept as that in the future communication will happen between you and I. "In the future we are talking." or "We are talking in the future." "talking" isn't temporal it's active. It can be future "we will be talking" or past "we were talking" or present "we are talking".

I'm sure there are some things which can't be translated nearly as clearly into English, but i don't think this is one of those things.