Yes, no doubt. But instead of throwing all your own work away try to save parts of it. Mostly the user facing ones, like the POS. Even Tryton has now a Sale Point module, I would look if it is possible to connect your own POS to it, so making the POS order and payment by your own POS through connection with Tryton. Easiest way to do that is using proteus but then using XML-RPC to connect (see https://discuss.tryton.org/t/log-in-with-external-script-fails/1525/11?u=edbo)
For the online part, if it is a simple ordering shop, it should be possible to use Flask-Tryton and create sale orders directly. But it seems your online shop is a webapp right? Then you can also use flask-tryton but then as intermediary between your webapp and Tryton. You can even move it a bit further and create an own module with routes where the webapp can connect to for data.
Also what other logic do you need? Try searching this forum and dig through the Documentation. Just setup a demo server for yourself, install modules and start fiddling around to get to know how Tryton works. Install more modules and see how far you can come. As an example, look at the production module a ‘production orders’ for your pizza bakers.
I hope you will get some ideas and hope you don’t make a false start with Tryton as well (did you know Tryton and Odoo both have OpenERP as there ancestor?).