When your script has high powers, it’s best to be mindful of the frame you choose to fit your lenses in. The higher the script the thicker the lens, so going small is the best option. This doesn’t mean you can’t get yourself a larger pair, but depending on how high your script is, you may get a lot of lens protruding from the rim of your frame.
As some background understanding, when a lens is made prior to edging (cutting) into a frame, it comes as a large disc 70-75mm in diameter. The focal point of the lens is in the centre of the disc, so if your pupil sits on the inside of the rim, then the outside of the lens will be thicker. Also depending on whether you’re a plus or minus power, will determine where the lens will be thick. Plus power is thick from the centre and thins out as it gets to the edges, where minus power is thick from the edges and thins as it goes to the centre.
Bearing all this in mind, the smaller the lens and the rounder will give you the best job irrelevant of whether its plus or minus. Also, having your pupil as close to the centre of the lens helps utilise the thinnest area of the lens. Even if the frame is slightly larger, if the lens is round and your pupil sits well centred, you will get a very good job cut out.
These days thin lenses are available, they come in index 1.74 and 1.76 and if you opt for a glass lens, you can even get a 1.9. At the end of the day, the most important thing is to just own it and enjoy your glasses. Within reason, get what you love and if the lens is a little thicker, that’s fine.