Having issues where my suitelet is loading very slow, like 9s to first byte before anything shows. Any ideas how to remedy this? Or make it load faster?

If it's a UI suitelet, you could consider changing it to a SPA mini-app. Though non-trivial it puts rendering speed back on the client.

It is a UI suitelet and it is not external. That is an interesting idea. I'll look into thta

we've done this with Angular and Vue and Aurelia in the past - quite a nice solution that runs faster and is more flexible than traditional Suitelets... plus it uses industry standard tech. Just leave NS to be a JSON backend (either via a data-only suitelet or a restlet)

@stalbert can you give me an brief idea on how to create UI suitelets with angular?

The netsuite file cabinet can serve as a static web host. We built a standard API interface that runs as a restlet or suitelet which presents a common json message format for requests/responses. So the data layer for the front end app is suitelet or restlet, the web app itself is just served up from the file cabinet. If you want/need the app to have netsuite's menu and stuff, you can host the web app in an iframe on a generic UI suitelet.