Replying to Next lens for Sony a6000

I've got a Sony a6000 with the 16-50 kit lens (meh) and need another auto lens. I've got adapters for a few old manual lenses ( 1.4/50, 5.6/400 and a number of crappier minolta manual lenses) but for action shots I feel I need another auto and a bigger zoom. Something along the lines of Sony E 18-200mm f/3.5-6.3 OSS LE.

I shoot surfing, skiing, and everything else really. Some instances where I felt limited were shooting surfing late in the evening ( hard to manually focus on the 50mm and not enough zoom at times, 16-50 isn't bright enough), bird watching (400mm is the only big enough zoom and am not good enough to shoot freehand and manual focus, plus sometimes too much zoom).

I guess I'm looking for a do everything (including video) lens. I don't have an unlimited budget as it's all recreational. Beyond sensor crop, is there a reason to not consider an older FE lens if it is in the price range?