Croatia is so easy to travel around, you don't need to be THAT prepared. But here are some observations/tips.

 Arrival to Split via plane.

The airport is small and easy. The bus is cheap and runs regularly and shows up in front of the one building airport when flights arrive. Don't waste $ on a private car. 

The Souvenirs.
Croatia makes nothing. They only thing they produce is limestone, which is too heavy for today's luggage weight limits. They do have tourist markets with purses and scarves, but they all come from Thailand, so you're better off just giving your mother, babysitter, kids, etc. a $20 and telling them to think of Croatia when they spend it.

The Food.
It's good. Really good. Fresh, fresh fish. Even the boring stuff is really great. There isn't much in the way of a signature food. They are equal opportunity servers of beef, pork, fish, lamb, veal, even chicken (though less) and always have a vegetable only option. There's an awesome, frequent side dish made of a green leafy vegetable that no one could agree was either spinach, collards or escarole, but it was mixed with potatoes and seasonings that were perfect. They're in love with carbs. No meal was served without fresh (but plain white) bread, and pasta, rice and potatoes were guaranteed to follow. You'll nevere need to reach for the salt shaker. Corn appears in random places. Like on pizza.

The Pizza.
Is abundant and very good. Croats like to brag that it's better than pizza in Italy, but they add that any country has pizza better than Italy.

The Prices.
The Dalmatian coast- existing almost solely on tourism is neither cheap nor a rip off. It's pretty fair overall. There is very little difference in the price of the same meal at a street side joint or a 5 star restaurant (and it is the same  quality at both). But a beer, a coffee or a slice of pizza are each only $2.

It's the norm, but not an obligation, and they don't seem to have an amount that's standard. 20% isn't over the top, 10% won't get you hunted down and killed.

It's primarily Australians and Europeans (heavy on the UK brand) and English is spoken absolutely everywhere, which is no good if you want to practice your Croation.  Oh, and they don't call themselves Croatians. They call themselves Croats (Cro-ots)

Skinny jeans everywhere.
The largest size jeans available in stores are too small for American size 8 thighs.

The Language.

C is ch (like iTCH)
Z is zs (like caSual)
And j is y (like You)
Accent signs signified something, but I couldn't tell what, since it all just sounded like a series of c's and z's.

With a capital zero. Other than seatbelts, they have very little in the way of safety precautions. No helmets on rocky bike treks. Cliffside railings were shaky if present at all. Steps were not standard. No signs were posted about ways to (or restriction of) diving from tops of boats. The only effort of safety was on the rafting trip, but 5 people had died on the river to cause that. The general laissez faire attitude is refreshing, as you're free to roam about and make personal decisions like grown ups, but again... Americans haven't been there much yet.

It's tourist destination. But do it anyway. You won't be disappointed!