Kryssa,

I've sailed there four times-- middle and southern Dalmatians (next trip will be Istria/north). Any questions for me?
Some observations:
First time I sailed Split to Dubrovnik-- too far, only allows for highlighting.
Has become much more crowded in last few years, but less touristy places can still be found: second time on Hvar and Brac, my crew preferred the secondary, less popular stops such as Jelsa and Supetar.
Vis is my favorite island; also recommend SIbenik, Pag, Mljet.
I know you stated you've reserved a cat, but a monohull, for quayside med-mooring, is preferable there. Also most charter cos. have more than one base; consider a one-way sail for a reasonable fee to see more.