What a bunch of great suggestions!
I'm not sure where you are located - but we've had several parties in the Central FL / Polk County area. This is what has worked for us, they've all been hits.
1st bday - chuckie Cheese in Lakeland - kids aged 1 (mine) to 10 - all had fun.
2nd) Mary Holland Park in Bartow - had ponies - Jess' party ponies from Mulberry - kids ages 2 - 11, everyone had a blast, played in playground, rode hand led ponies through the shaded pine tree area, served food in a pavillion - reserve through Bartow Parks & Rec.
3rd) - Bowling party - they all do it, but ours was @ Orange Bowl in Lakeland - kids aged 2 -12 + adults, pgk included private room, pizza, beverages, shoes, 2 or 3 lanes and 2 hours of bowling. Everyone had a blast.
4th) Puppies & Ponies party - back @ Mary Holland Park in Bartow - same ponies, + payground + party favors were "build a bear" STYLE dalmation puppies (found online) - in red bags, had "stuffing party" @/near the end of the party - everyone LOVED IT.
5th) Back to Mary Holland Park AGAIN - rented big pavillion, hired face painter / art student - had "Fairy" party - made fairy skirts, tutus, wands & halos for each girl - that + treasure bag w/ mini bottle of fairy dust, some chocolates and good luck token were the favors.
Also -in Lakeland there is a place called Backyard Adventures - it is an inflatable / bouncy place - or Mad Science, or the Children's museum. In Winter Haven - there is T&R's Funhouse - like a Chuckie Cheese, but larger, cleaner, not as expensive, not as crowded.
Good luck & Have fun!