The idea of Hearts' Game isn't bad, but the execution is fundamentally flawed. If I had to pick a single design decision as being at fault, I'd say that accomplice selection being a sequence of three random draws was probably the worst decision. Personally, I would have gone with a system where accomplices were divided into various roles, then a random pool was generated containing at least one of each role, with players having to select three accomplices from the pool.

Players having minimal control over team composition and being largely unable to make strategic selections does not mesh well with the game having some of the hardest stat challenges in existence (harder than endgame content like the Tracklayers' City, for example), or with the pool of possible actions being based solely on your team, or with your currently available actions being a random draw.
In short, Hearts' Game is a perfect storm of incompatible gameplay elements, and tweaks like increasing hand size were the equivalent of a band-aid on a sucking chest wound.