Button colour is not a test. With limited traffic you get a handful of experiments a quarter, so spend them on changes large enough to matter.
1. The headline promise
Test outcome against feature. It is the first thing read and usually the largest effect.
2. Form length
Remove every field sales does not use in the first call.
3. Proof above the fold
Move one specific result, with a number and a name, next to the headline.
4. One call to action
Strip secondary links and navigation from paid landing pages.
5. Price visibility
Showing a starting price lowers lead volume and raises lead quality. Test which your sales team prefers.
