I'm not so sure - wasn't it more related to the need to re-structure the Army after the First World War and the contracture from huge conscription army back to full-time professionals? (Too many generals post-war...?)
In many ways, it seems not unreasonable that the resulting rank of "Brigadier" which succeeded "Colonel-Commandant" should stand alone as a senior staff officer commanding a brigade and the sequence of insignia from major to brigadier with Crown plus increasing numbers of Stars (pips) seems entirely appropriate to me.
Personally, the use of the sword/baton insignia alone for the former rank of Brigadier-General always looked slightly odd to me - somehow it seems to beg to have something else added to it.
If you wanted a truly numerical system then maybe the army should use a parallel system similar to that of the Royal Navy where the presence of the sword/baton under a Crown would indicate Flag/General Officer rank and a sequence of stars (pips) below this indicates actual seniority...? I say this with tongue somewhat in cheek but it would certainly make the international recognition of these ranks much easier...!