Had to book a last-minute flight with TAP today -- thanks for the info, this thread has been helpful!
Confirming also that as *G, I was able to get a baggage allowance of 1 bag during online check-in for BCN-OPO-LCY, even on a Discount fare. It is still making me pay to change my seat at T-8, although the system did seem to auto-assign me to preferred seats in the front already. Will see whether I can change it at T-3 as previously mentioned in the threads.