Again, gorgeous design, but there are some genetic issues.
Everything looks good for coat colour, except for the splash and double cream gene - only one of the parents was a cream gene carrier, so your foal would be a sooty silver buckskin, not perlino. Also, minimal splash (which is represented by heterozygous splash genes) would be limited to markings on the lower face and legs, and would not extend up to the belly the way that a full splash marking would. Since both parents are splash carriers, you could change the genotype to SplSpl (homozygous splash), or change your markings to match the heterozygous genotype that you put.
I know that the genetics I designed for horns can be a little complicated

A purple base and ivory both work, but the rest of the genes are a bit off - if the foal is a shade carrier, I ask that you show that he is heterozygous (Shsh instead of just Sh). Because only the mother is a pale carrier and stripe carrier, the pale and stripe genes would also both be heterozygous (Pp and Stst). Only one copy of both shade and pale would be present, so they cancel each other out, but are still part of the pony's genetics. So the horns would be ivory with regular purple stripes