Is it ok just to do the front plank and the glute plank?

I find with the front plank, I really can do it right, and get a good ab/core workout. Same with the opposite side, the glute plank, my but, hamstrings and lower back feel worked.

With the side plank, I cant seem to do it right, and it seems to almost cause pain in my hip. (I cant really pin point the pain, it's just there)

So is it alright to just do the front and glute plank. Are the obliques that important?