I suppose the Mantic Skeletons are an acquired taste, but I happen to like them, and
have found that with a bit of work, they can look really great. I actually think they're still one of Mantic's better lines, even though they're by now one of the oldest. Once you get to know the miniatures, there is actually a surprising amount that can be done in regard to posability.
As an alternative for the GW skeletons, they were pretty much the only plastic offering back in the day, until the advent of the Wargames Factory skellies.
But those received just as much flak after release, but now not because they were so clunky and would never fit inside a living human (GW), or their limited posability and slightly cartoony Army of Darkness aesthetic (Mantic), but rather, they were now too fiddly and difficult to assemble.
To be honest, the only plastic skeletons I never liked of the above were the original GW ones (the newer ones were a great improvement though). The Mantic ones I actually loved
because of their Army of darkness look, and the Wargames Factory (now Warlord) ones were retooled, and are now a lot less fiddly to glue together, while still maintaining that Ray Harryhausen feel. And while they are thin and look fragile, I've not experienced this to be a hindrance myself and they are quite a bit more sturdy than their feeble looks would make you believe.
The Mirliton skeletons are more in line with the old GW plastic sculpts in regards to aesthetic and clunkiness. I agree that they are all sculpted very much (un)'alive', and will probably survive the rigors of tabletop combat much longer than the thin Warlord ones though.
The sculpting back then was obviously a compromise of the above; looks and toughness. The thinness of the WF skeletons is simply not possible to achieve in other mediums such as pewter or resin, so they were sculpted thicker to accomodate the material.
Hence certain lines will not be as aesthetically compatible as we'd like, and it's down to personal preference and/or matching existing collections.
I certainly like the Mirliton skeletons, but they do not match my painted ones, which are mostly Mantic. this is also the reason why I eventually did away with my Rackham Confrontation skeletons; they were just not a good fit (too tall and also too bulky, too thick weapons etc).
But if you like the Mirliton ones, might I also suggest
GW's (OOP) Armoured Skeletons by the way? I think they would match up pretty well...