I rather watch a nicely done tweened animation than a mediocre frame-by-frame one.
Frame-by-framing is hard, it might looks better but that's if you do it right. If you suck at drawing or animating, you should start with tweening and then add fbf here and there. With time you'll get more comfortable and you might start adding more and more fbf.
Now let's be realistic, you're not a huge studio, you're just a single guy doing the whole animating. Making a 100% fbf animation is really hard, it takes time, you'll probably get tired of it and kill someone in the process. Just try to combine fbf with tweening first, maybe with time you'll get enough resistance to handle more fbf till you become the next Happy Harry.