I suppose that is the peculiarities of personal preference. I find the Semogues suffer from disappearing lather and they become floppier much quicker than other boars - that and the construction of their knots which are glued into a conical cup to make them splay - excessively so. The face feel though is excellent from the fatter bristle that they seem to source. Zenith bleached boars use a much finer hair but are lofted too high and feel like a mop - their unbleached boars are very good though. Now a short-lofted Omega's on the other hand hits the goldilocks spot. In any event I find boars are a disposable brush in that they hit their peak for about 6-12 months after being broken in and then become increasingly mushy there after. But when a boar is at its peak and being the best it can be - just tremendous.
I've not used any Semogues but your observations of bleached and unbleached Zeniths fits with mine, I really wish their unbleached ones were a little easier to get hold off as they are truly delightful to use.
I've owned quite a few Omega boars and they are incredibly variable for consistency. Even though I have enjoyed using them all at times, I don't think I'd buy another one.