I want to throw my 2 cents in the ring on this.
What I would like to see as a new feature is likely something most merchants would not care about, but I think it would be instrumental in pushing thirty bees forward in the future and expanding the base with more developers and larger tier users.
1. Push a change to how modules store data. I think this will get a lot of push back, but I think its needed for the end result. I think modules need to start adding columns to the default tables, with maybe more default tables needing the be added. Say you have a module that displays a custom section of text that is editable on a per product level. Like a module that hooks under the productextraleft that says "Free Shipping" on the front. I think that module needs to quit relying on its own table and store in the tb_product_languages table by adding a column.
I think every possible module needs to start extending the default tables and storing data there when ever possible,
2. I think the current webservice needs to be left as is, completely compatible with prestashop, but a new version 2 needs to be built out with a different end point. But instead of building it like the limited webservice that prestashop has, build a really extensible, resilient api. There are a ton of limitations with the current webservice, its only good for getting (some) data and storing data.
What I am talking about is bringing everything online with the api. It needs the ability to build carts, query the api for shipping prices on those carts, get payment gateways, pass payments (which I do understand the modules have to be written to support this).
Where the adding columns comes in, is in the resiliency of api. Where someone working with the api can just get product id -> language - > moduletext. The idea is when a module is added since its adding a column to the table, that new column becomes available in the api.
Bringing an api like this online and making 100% of the core available through the api will expand the thirty bees universe more than anything. Look at PrestaShop, they are working towards a better more modern smarty integration, taking logic from their templates, ect. But in the end they are ending up with the same thing, just organized differently. Bringing the whole api online will make it possible for thirty bees to be headless, which will open doors of new technologies as the come out. Want to run a node front end? Sure, you can. Or React? Ok. Static html? Yeah, that would actually be possible.
That (those) are the features I think need to be added.