The scoring disparity among different apparatus is always a problem.
On floor, there are always combination passes to narrow the gap from huge tumblers. Adding extra dance further narrows the gap.
On beam, higher difficulty comes along with extra risk. Part of the extra bonuses earned by cv are taken away by rhythm deduction.
On vault, as the start value decreases, the quality of the whole field also decreases. The gap between an Amanar and DTY / Y 1.5 is shrinking. Still the gap between strong vaulter and weak vaulter is wider than the floor / beam equivalent.
Bars has the widest gap among all apparatus but shits can happen (e.g. hitting low bar, -0.5 handstand, rhythm break). The downfall of Romania is partly due to bars.