That's my point though. Why add dragons into a game if you're going to go the easiest, most boring, and least interesting route possible with their gameplay. Why even add a dragon brawler if you have the main character? There are just so many design decisions in the game that seem baffling and counter intuitive to me. The other more obvious problems are things like very poor hit reaction and detection, very limp long range gameplay from both the dragons and the human character, etc. etc. There were a lot of problems and it was a stark contrast to what something like Nier Automata showed off with its boss battle.
Well, lets take your example.
Why even add a dragon brawler if you have the main character?
I cant help but feel like your thinking of the game too much like another action game. The main character will support builds just like any other RPG you have seen, He can take a far away approach, use the bow and arrow and lay traps for example. You can use the melee focused dragon to handle CQC while you set up.
Don't like bows and arrows? There's a Ki blast that's basically some Yusuke Urameshi type shit if that's more of your thing.
Don't like fighting from a distance? Okay, say you use something like the greatsword or the spear. With the same build you mentioned, you can tune your dragon for speed so that he can cover your openings while using such a slow weapon, or make him a metal covered death dragon with a giant blade to rain down the pain while you cover his openings with the faster weapon.
My point is, Scalebound is an A
RPG. What you may see as pointless may be a build someone else comes to love. Having variety is (almost) never a bad thing. The whole point of the game is this development of a bond between the two protagonist, and I feel that's a much more interesting idea, especially in the way it manifests in gameplay. I could relate to your point if the game was ever made out to be something like Panzer Dragoon or something more focused around controlling your dragon directly, but even in concept phases it sounded far more similar to something like The Last Guardian.
I also think the gameplay itself looks fun as hell, so there's that.