Upkeep is too low.
That's my view.
This isn't just about melee-ranged hybrids, it's also about any kind of hybrids, say, cavalry-melee hybrids. In Native, if you picked cavalry you were crippled in melee. If you picked archer you were crippled in melee.
I know I know, many will now say how horrible this upkeep is, and that they can't afford anything. Unfortunately, if archer can afford the best bow and the best melee weapon, or if horseman can afford best horse (sarranid/courser), the best cav weapon (heavy lance), top infantry weapon etc.. then there's nothing wrong with hybrids. It simply means people have too much gold.
Now the only question is do we have too many of these hybrids or not. Because there's nothing wrong with the idea itself.