Hey... new user testing Affinity, also looking for the definitive alternative to Illustrator. Not only A***e suite is prohibitive expensive, but it has become a slow and unusable Jurassic beast, slowly doing his last steps to the extinction. With latest updates, open any small file can last for 10 minutes, being screen freezes, colour ball spinning, and lagging, the constant norm.
About deformation tools. The only decent ones i remember used, were from my beloved Corel Draw... even in the first 90's, it had intuitive and easy to use tools, that I'm still waiting for Illustrator (by the way, Illustrator "Free distort" tool is an absolute joke)
So, alternatives inside Affinity... just I found an interesting tab capable to adapt any object to an Isometric view. It's not the real solution to "warp", but surely can help to create some technical illustrations. Below the screenshot of the tab options.