You'd want to keep an eye on t3, t4 and tsh for your thyroid functions. If the tsh gets above range, even if t3 and t4 are in range, it means your brain isn't seeing the response from you thyroid that it wants so it ups the signal to increase production. That can happen with long term gh use. Some folks just add in a bit of t4/levothyroxine to counter act this. Others just take intermittent breaks from gh for 4-6 weeks and let their body get back into range again.

For glucose/insulin sensitivity you're going to want to pick up an glucose monitor and keep track of your glucose levels. You can get one off amazon. There are better people here than me to tell you about how to counteract any issues that arise here. You could make a post in the proper forum. But chances are it's already been asked and answered dozens of times. So maybe just do a search for glucose + gh and see what pops up. I do know berberine can be used to help stabilize glucose levels. But dosing and timing aren't something i can answer for you.

Most people don't have issues even running gh long term when it's just a replacement dose of 2-3 iu per day. You start cranking up the dose you're more likely to have issues. So try a search and see what you come up with for answers. If you still have questions you can't find the answer to make a post asking for guidance.