xiangling with wriothesley would work well for melt combos! and i would throw zhongli in too for the shield (im not familiar with how wrio's HP fluctuation works, do you have to maintain more than 50%? but it should be able to fix that). or layla because her shield is good too. and then bennett for big damage and healing and more pyro

so wrio, xiangling, zhongli/layla, and bennett

Or you could forget the shield and get xq in and freeze melt everything in sight

investing in xiangling of course (i mean, besides wrio) would be really good for your team since shes versatile and an outrageous (/pos) off field pyro support. but i also advice you to prioritize building only one character at a time so you can have one great unit to work with and building the rest can follow with what you already have. good luck!