it's tough to see any batsman from any country finishing their ODI career averaging 50+, even more so for a top 3 batsman. hussey couldn't even manage it. 50+ in tests could happen, he seems to have the temperament and the talent but does need to work on some technical issues but look a lot of players with technical issues average 40+ and even some 50+ in tests e.g. dilshan and sehwag.
tamim could average 50+ in tests, i know anamul has a higher output for tons but tamim has always been a solid FC batsman, averaged 40+ from the very start if not very early on in his FC career and has never dropped it below 40 and he's averaging nowhere near 50 in tests or ODIs and you can't say he doesn't have the talent.
it's a bold statement to say anamul will finish his career averaging 50+ in the 2 major formats, and it's something i'm very much intrigued and interested to follow throughout his career to see whether he can do it. it would be a huge step for BD cricket if it was to happen.