As for the first one, You might want to try out a few public markings:
- varnish blanket + spots from Eldervine's marking set
- markings 3-6 by Farai: http://cheshirefarms.weebly.com/cc-blog/appaloosa-patterns
Others that might be useful are Farai's varnish roan face and leg markings, not to mention mottled skin that's useful with all kinds of appaloosa coats
I've found it's usually the matter of playing with various markings, freeform ones are often very helpful.
As for leopard... Well, these are tricky, you best bet would be to try making one with freeform spotted markings, or try and create a custom marking from scratch - which is tricky and very time consuming.