Tropical glaciers can be found (or could once have been found) not far from the equator in Papua: [Ngga Pulu, just under 16,000 feet high, sports an ice cap](https://earthobservatory.nasa.gov/images/91716/glaciers-in-the-tropics-but-not-for-long).

As for the steepest elevation, 30,000 feet may not be completely realistic but you might take inspiration from [Mt Thor, Canada](https://en.wikipedia.org/wiki/Mount_Thor), the steepest vertical drop on Earth at 4,101 feet:

![Thor Peak, Nunavut, Canada](https://whenonearth.net/wp-content/uploads/Mt.-Thor-Canada.jpg)

The cliff was created by glacial erosion scouring a steep wall as it formed the adjacent valley. The cliff's angled at 105° or more vertical than vertical!

To get your 30,000 feet you'll have to do some planetary engineering: lower gravity to start. See: [What is the highest possible mountain on an Earth-like world?](https://worldbuilding.stackexchange.com/questions/99157/what-is-the-highest-possible-mountain-on-an-earth-like-world).