Hahnemuhle has profiles available for the Epson 11880 for those papers. Their profiles are based on Velvet Fine Art for Photo Rag Satin, and Premium Lustre (260) for the baryta - logical starting points for your profiles.
The Ilford paper sounds very similar to both Exhibition Fiber and Fine Art Baryta. I believe most recommend using Lustre 260 for both of those, so that's what I would try for the Gold Silk. I would suspect they have profiles as well for Epson printers, you may dig around and see choice they base their profiles on.
The paper choice sets up the basic options that are available for particular paper types, (such as the dpi quality settings), as well as the basic values for things such as the platen gap, drying time per pass, paper thickness, photo or matte black ink, suction strength etc. as well as how much ink load the printer is allowed to print. On some papers tweaking those may improve results which can be done in the paper configuration dialog box. Some recommend changing the platen gap to widest or wide if their are problems with streaks or smears with these new thick papers, however, on my 11880 with Epson Exhibition Fiber the default as worked quite well, and I would expect the hahnemuhle and ilford papers would be quite similar.