My two cents is that UI updates hold very little value personally. I'd prefer to see that the codebase was being maintained and that a few better options in terms of managing collections in bulk was supported. I would be happy to sell in ongoing license support and upgrades to clients as an option. Perch is still one of the fastest and flexible CMS's to set up and I can reliably get very little support requests in terms of managing the CMS once it's set up which is a big win for me, as well as having very little maintenance burden.
Composer support would be great, as I have implemented my own solution to keep core maintained via composer on the sites I work with most. I'm not a Perch shop (most of my work these days is with Shopify) and for very small marketing sites I will go the Netlify CMS route, where I only need to offer the client small tweaks to a very static site but without having to set up a server. I've used and evaluated other CMS's but I have yet to find one that client's like as much. So I will always pick Perch for a site that requires regular client updates, but does not require constant development.
I have been watching this thread - and silently hoping to see some positive developments / updates. Love the product, and appreciate that the landscape has changed and Perch needs to adapt to that 👍