Trying to build 2D grid and Desk layout customization for new ERP

As per discussion on this link. We are building a different new ERP system for a different set of industry. We want to brand this ERP as our so we have not used any erpNext on it. There are few things that has not made Frappe our main framework.

Some of the things that I would like to talk about are :

  1. We want to implement our own design system into desk, with bigger font size and some bootstrap or tailwindcss? How do we customize this?
  2. We want to have a 2D matrix data representation (optionally with realtime support) so that fields can be updated as per row header value and column header value. This is the business use case. We already have such layout in our Flutter app which saves the data into SQL tables. If I want to have such features self implemented how do I do it with HTML field type instead of making whole page for this?
  3. Rebranding and UI customization is necessary if we want to sell this product. Frappe already provides alot but I cant seem to find concrete doc for this. Client scripts and server scripts are way to go?
  4. Overall nice framework but again if I am to contribute to this open source project, I need to have the ability for better garsp of this framework which honestly the extensive documentation lack.