Best way to get some bass energy without mud is to put a high pass filter on somewhere between 35-50 Hz and follow that up with a low shelf somewhere around 90-150 Hz. I am being rather generic with my answer here as it is always dictated by the material. The high pass will cut out unnecessary low end and the shelf will bring up the desired frequencies above the high pass. Play with that and see what happens.
What are you using for listening when you are mixing? A good pair of low end monitors in a treated space will do wonders for you. it sounds to me like you might be mixing with headphones or with some speakers that are boomy, although that is just a guess. I know I used to have this same issue and had no idea how it was leading me to either cut too much out of the bottom or add too much to the top.
Anyway, this is just a general approach to take. You are on the right track. Keep making music! :-)