Good point! I was talking about noImplicitAny; strictNullChecks is worth the 'hassle' from the start.
Dealing with other people's modules has also gotten much easier in recent versions of Typescript. To define a module name as any-typed the boilerplate has shrunk to a bare minimum:
declare module 'name-of-the-module'
Even better, module names in recent Typescript versions accept wildcards: declare module 'some-big-node-library/**/*'
declare module '**/*.css'
declare module '**/*!text'