Orthodontics to lengthen teeth

My bottom teeth are crooked and my top teeth, although straight, are different lengths. This was always the case but has been aggravated by bruxism. Ideally I would like to use Invisalign to correct the crookedness of the teeth (only minor). But more than anything I would like to use either Invisalign or braces to relengthen and then shave the jagged edges of the teeth so that they are smooth and even as well as straight. Although crowns, veneers or composite fillings are an option, and some dentists have said they are happy to do this, others have said that because of my bruxism it would not be worth it, and I should just accept that I can't do anything but wear a guard and prevent further wear which I have already done for some time. My question therefore is, could Invisalign or braces achieve this aim of relengthening as well as straightening worn teeth, and would it be preferable to crowns? My teeth are healthy and it seems strange to damage them to make way for crowns and veneers.