What business pain points aren't being addressed well today?

It sounds like you're in search of a problem with the intention of developing a solution, which is great.

I find though that B2B solutions generally require extensive domain knowledge and likely network connections. In fact, many B2B software companies are started by someone trying to scratch their own itch.

Have you encountered any business challenges that you may have more insight on than the general public?

Regulatory compliance. How can I know what laws are applicable? Accessibility, taxation, privacy, record retention, etc. are all areas that I think many businesses could use help.

Same day closing. Gartner talked about this 20 years ago. ERP and accounting systems that do not require 4-8 weeks to close the books every quarter.

Same solution for scenario planning. What is the impact of a sole supplier in Thailand deliver just in time being flooded out for 3 weeks?

What happens to the bottom line if days outstanding receivables grow to 54 or 90?

Localization is probably one of the most expensive business processes that return the least bang for your buck.

You can also never go wrong targeting sales. A business may not give a rip about time wasting nuisances, but even in the worst quarters the sales team always has a seemingly bottomless pool of resources to throw on prospecting tools.

The best idea is to work on something you are passionate about.