This makes sense to me. Two-Bad has never really been depicted in a manner that really warrants him to be a significantly bigger figure. In both the 80s and 200X MOTU toylines and corresponding cartoons, Two-Bad was roughly a regular-sized character in terms of height and proportions, with the only difference being the wider upper torso and two heads. His arms, legs, heads, etc. were all of average size. For this figure, they can likely easily reuse a decent amount of the existing tooled parts for the lower half of his body and his arms. Plus if they ever give us Tuvar and Badra (something that may not be likely given the shaky ground that the line is on, but not entirely out of the question), they can then reuse some of the new parts that they will make for him like the heads, any unique tooling that they made need to do for his hands, boots/feet, etc.
Ram-Man is quite a different case. In both toy lines he was a completely unique tool with proportions that vastly differed from most of the other figures in the lines (I know 200X was mostly unique tooling on each figure, but the point remains none the less). In the Filmation cartoon, they kind of made him short and stumpy looking.... almost like an over-sized dwarf or something. While I am a big Filmation fan, he always looked odd to me in that cartoon for that reason. In the 200X cartoon, he was a really big guy! He may have been depicted as taller in that cartoon (I'd have to go back and watch it again), but even if they were to make him the same height, proportionally he was just very different from most of the rest of the characters. And his 200X figure was kind of 'dinky' with the size that they made him.
IMO from what I can see of it, the MOTUC figure kind of creates a happy medium between all of these aspects of him. It was the only way to do him justice. Like the rest of the figures in the line, he will be roughly the same height, but he will retain his proper proportions. He makes sense as an exception to the rule IMO.