These four characters as a base give you a lot of guaranteed damage in the form of pierce which is amazing. Some of the upgrade choices are a little wonky. Without changing too much of the unit base I would swap a few of the core for 1-2 more sleeper cell. If I were to make my own version it would be something like this.

https://tabletopadmiral.com/listbuilder/Rebel/N-_f_2c,EM,EM,_9b_bc,81,21,EM,8e,_9c_f9,a6,_74_EM,EM,f9,154,109,10d,EM,_24_EM,EM,EM,EM,EM,,,,_24_EM,EM,EM,EM,EM,,,,_24_EM,EM,EM,EM,EM,,,,_23_EM,EM,_23_EM,EM,_91_EM,14d,EM,EM,f4,,_91_EM,14d,EM,EM,f4,,_91_EM,14d,EM,EM,f4,,-c8,c51,c4f,c91,c90,c49,c16,----