> agents seem to perform worse when forced into certain architectural patterns.

FWIW I've noticed this too. I've found that the agents/models have their own style, which is mostly summed up as overly verbose.

Additionally, the models are OK at modularization when given space to "plan" their implementation, but rarely decide that abstracting something would be helpful after the fact (i.e. after many iterations on a greenfield codebase or when being dropped into a legacy codebase).

This often leads to "god files" which, when pointed to by the user/architect, causes the models to correctly critique (humorously when they're the ones that wrote the code in the first place).