There is something about landing pages that scratches all my itches - creative design, analytics, technical, direct marketing, helping connect customers & solutions - all wrapped up in one little web page.
Other than the usual landing page templates you probably already know about, here are 3 tools that I find useful that can help you:
Unbounce Landing Page Optimizer: Learn of trouble spots by comparing it thousands of other landing pages
Attention Insight: Instant AI heat map of your landing page, even before you launch
Google Optimize: Free A/B testing
There are some articles in the Landing Page issue of the Scrappy MarTech newsletter you may like as well: