Agreed that it's overkill for most use cases (in fact I mention that it's not ideal for most people and we're likely an edge case).

As far as putting a great deal of code into Lua scripts, we'll be putting together a few blog posts explaining how we make this manageable. We were able to double our API throughput by shifting this direction so for us this is worth the difficulty we faced in finding ways to modularize and reuse code in Redis Lua scripts.