I like that idea. Instead of having a specific topic like sales, we can target specific type of makers/businesses that face specific challenges.

In addition to the ones you mentioned, some other ideas:

• E-commerce
• Content / publishing (e.g. BetaList)
• Enterprise-oriented
• Platform-based (e.g. built on top of Shopify, etc)
• Mobile-first / mobile apps
• Marketplaces
• Browser extensions (e.g. Grammarly)