This is fantastic feedback, thank you very much for taking the time to write this up.
We totally agree with the points you have raised - in fact we are in the process of addressing the component deletion problem; providing the ability for users to delete components with the keyboard or use an action bar that will be shown in the preview.
As for mapping data - this is something that is requested a lot and as such is high priority. We will be working on this in the coming weeks, providing full JS support and transformation logic for any source of data that you fetch from your Budibase applications.
Great to hear you had a good experience using Budibase self hosted. We are constantly trying to make the Budibase setup process easier, both through our self hosting setup CLI and through standard deployment configurations that developers are used to - such as docker compose and helm charts for kubernetes. Which method did you use?
Please do continue to follow Budibase - We are confident that you will love the features we planned on our roadmap for the next few months!