I've played 5 games. My first game, I couldn't fish at all, and I still had a great time. The way the game was developed, you can play any old way you want, focus on anything you want, have any goals you want. This was made still clearer in later versions in which the developer offered players choices of layouts that focused on various things. For instance, you can now choose a layout that has lots of river and very little space for farming - which of course offers plenty of fun for fishers. Likewise, you can completely avoid combat, monsters, and magic if that isn't your thing, and just have a magnificent farm. Or you can focus on those things to the detriment of farming. Some people just really seem to enjoy decorating and design. Somehow over the years a lot of people have got the impression that you have to do everything, have to meet all goals, and so on, to "win" the game. I'm doing that right now - and loving it - but it certainly isn't necessary. Winning is in the eye of the beholder. I guess pleasing "Grandpa" has put a lot of pressure on players, but of course pleasing Grandpa isn't necessary, either. Nor is it necessary to finish the Community Center as quickly as possible, or rush to the bottom of the mines. There are so many ways to play the game. And if you feel like starting a new game, you can do things differently next time.
So no, I literally can't imagine running into a "wall" with this game. It's an open-ended, organic game with a universe of possibilities. Much like life. For instance, later on, you may decide to start fishing, and then you'll have a whole new world to explore.
I don't know what fishing mod you got that is buggy, but my fishing mod has worked great. Are you on a PC? Can't you remove that buggy mod and replace it with one that works?