If I'm writing new modules/pipelines from scratch, should I try to make them use strict syntax and typing by default? Or should I just make a regular module and convert later?

Strict syntax is already a requirement for nf-core, so you will save yourself some headache if you use it (and it's better anyway). Typing is not yet officially introduced, so feel free to play with it, but for now ship untyped modules to nf-core repos.

Typed processes (NB different for params) are in preview until October still. I hope we will adopt ASAP after that in nf-core.