there are pretty much no substitutions. even gems from gemini which were similar are also about to change to skills. for some of us there are certain custom gpts that are just not replicable with skills. 2 of mine in particular i am going to have to either hire a programmer or give up most of my business altogether as it was more than a custom gpt. the creator had done some programming on the back end to make it work consistently for a certain workflow. since it made up for a significant executive function disability i have, that business is gone.

if i only wanted to use skills, connectors and plugins well i was doing that before ai came along. there's not really any point to it now for me.