It's not painfully slow but you could cache the HTML pages instead of rendering them dynamically on every requests
Hm... That's a point, but I'm afraid it's not, well, portable. The engine acts only as a input/output component, that way it can serve as a back-end for multiple front-ends (a webapp, a MVC server, a terminal client, etc), I would prefer not to embed front-end specific content into the engine itself.
caching reverse proxy
I could cache the static HTML but then the user would not be able to operate the page correctly without restarting the page and loading the content through the javascript normally.
I'm also curious about the reason for choosing the Hunchentoot web server over woo/clack*. Lack of documentation?
Documentation is a point, also, hunchentoot is more old/stable, but the main reason is that hunchentoot compiles on my raspberry 1, woo/clack doesn't, kek. My original plan was to run the engine on my raspberry 1 for tests, but I assembled an old PC I had (pentium IV 1.5ghz, 2G of ram), I could use clack or woo if I wanted, but choose not to.