I loved the Fighting Fantasy solo game books and the Warhammer Fantasy RolePlay 1e ruleset. Both games were British and both oozed with flavor. I spent as many hours reading the WFRP rules and source materials as I did running it, and I ran a campaign of WFRP. It was a blast.
I own the Warlock! rules. I grabbed them last year when they were released. They are simple and fun. I really should mine them for some SWCL inspiration :)
Warlock! is today's Deal of the Day. Normally 14.10 in PDF, until tomorrow morning (5/16/21 @ 11 am Eastern) Warlock! is on sale for 2.77. All I can say is it is well worth the minimal investment for the pure joy you will likely get in return. There is a reason it is a Platinum Bestseller in less than a year's time.