I play this exact build, but with Vampire instead. I find the sustain it provides is just too good. Auto attacking is what we do so you are always getting benefit from it. Once I've got it and first aid I no longer have to hearth or drink from fountains unless I've been going full HAM using my other abilities fighting over an objective.

Once you hit 16 the extra range isn't as useful anymore due to graduating range. The 100% range on it is so far that I don't feel that I need an extra 20%. I can set up outside the range of an enemies core and attack any heroes that aren't just hiding behind it.

Other than that I love this build though. After 20, anyone within my range dies. It's extremely rare that my team will have to make more than a single core push.