Not so fisheye
The reason why this is not so fisheye-looking is that you hardly have any straight lines in the shot. Straight lines give away the fisheye effect most.
Trees also get bent and distorted but they can be crooked anyway.
In fact the only straight line in this image, is the "horizon" (i.e. the waterline) and if you keep that roughly in the middle of the frame like you did, it stays pretty straight.
The late Bill Bootstrap used to pride himself on being able to shoot fisheye shots that looked really natural (non fishy) without using defishing software. I've looked at his style long and hard (mine is completely different - I like to flaunt the fisheye - but I like to learn from the best). And the main recipe of Bootstrap's Special Sauce was the avoidance of straight lines near the edges of the frame : a horizon was most often smack dab in the middle in his FE shot. And if there was any straight vertical, then he would place that also in the middle.
Once you have found out how to make your FE shots look natural, it depends on your character and temperament whether or not you want to continue using that knowledge, or to throw it overboard and go over the top with your FE.
I'm curious to follow your next moves.