Paladin has been around long enough to catch on though and have you wondered why it caught it? It was not a massive leap of faith from the what it was based on into the game rules.
There have been literally hundreds of classes that have been made in D&D yet only 3 have caught on to make it into the PHB since AD&D. They are the Sorcerer, Warlock, Barbarian and I think a lot of it has to do with the names as you have a reasonable assumption what you are getting off the name. A name doesn't have to be perfect (see Druid), but the tie in has to be somewhat reasonable IMHO (see arguments over the Warlord name). Druid Celtic priest- D&D priest not a massive jump.
THe gish concept is fine the name is really hard IMHO, Duskblade and Swordmage for example not great names although Swordmage is better than Duskblade at least from a naming PoV IMHO.
I don't disagree with that. What I disagree with is the idea that you can't link the usage of arcane magic to a group of people who didn't actually use arcane magic, especially since the overall story they were involved in had a mystical tone that translates well into arcane magic in D&D terms.
I'm not exactly married to the idea of using that name, but what I'm trying to stress here is something a lot of people are missing, and that's what's informing their arguments -
the concept for the Argonaut is not "fighter-mage",
in the exact same way that the concept of the paladin is not "fighter-cleric". It's something altogether different that can best be approximated by calling them
professional adventurers in the same way that paladins are
chivalrous knights. IMO, having training in both fighting and magic (and tools as well) is sort of implied in the skillset of being a professional adventurer, and being a magic-user is a small part of the overall identity, not the defining aspect of the class. Hence why they are half-casters and not full casters.
The reason that Paladin has stuck around while no fighter-mage class has is
entirely because the paladin is build off of a really inspired concept, while fighter/mages never have been. This is the crux of what I'm trying to discuss here, and the majority of posters in this thread are simply not getting it. They are instead understandably encountering cognitive dissonance in trying to link the term
Argonaut to their established ideas of what a fighter-mage class looks like (i.e. 4e's swordmage), which is completely missing the point. Or, rather, it's demonstrating the point I'm trying to make.