[hadley]

(1) You might want to check out https://github.com/t-kalinowski/Rapp by my colleague Tomasz

(2) I think part of that is in scope for strict (https://github.com/hadley/strict). You might also be well served by adopting some more data validation tooling, e.g. pointblank (https://rstudio.github.io/pointblank/).