Toivottavasti = hopefully
kuulen = I (will) hear
sinusta = from you (of you)
todella = really
pian = soon

"Minulla on kova ikävä" really means "I miss you terribly" or "I miss you a lot".

Finnish is a very "down-to-earth" language - it is more normal to under-state than to over-state things. And feelings are usually among the things, which are difficult to talk about. This was only sort of cultural background on the Finnish way of communicating. But please feel free to be more emotional - for foreigners that is allowed. The attitude is getting more lenient towards "born and bread" Finns, too.