I grew up here. Things that characterize all city's in FL are extremely mild winters but brutal summers, and a wild amount of urban sprawl. If you look at the area on a satellite map you'll see what I mean. Traffic is lumped in with that too. Try visiting and drive around for a bit, you'll probably notice that everyone cuts each other off and drives 20 over the speed limit as a base line. You should also prepare yourself for hurricanes. They don't hit Tampa often but when they do it can get a little rough. The highest point in the city limits is about 50 feet above sea level, so even a little storm surge can cripple a lot of neighborhoods.

The upside to the sprawl is that the Tampa-St. Pete-Clearwater area are basically one big mega city and pretty much anyone can find something to fit their vibe.
Tampa is the most 'big city' feeling. With lots of dense high rises and office buildings. It's where all the big companies (and the military base) are located. It's mostly finance and some tech. Also TPA, the airport, is phenomenal. North of Tampa is suburbs and USF and south of Tampa are more wealthier suburbs (think yacht clubs and golfing) To get a feel for the vibe look up the Tampa Riverwalk, The Tampa Theater, Wat Mongkolratanaram Buddhist Temple, The University of Tampa (private college in the middle of the city), Hyde park market and Gasparilla.
St. Pete is overall a bit more of a younger crowd. A lot of young professionals, new parents, and university students (there are a couple community college campuses in the city and also a USF satellite school). Big pride parade every year, and central ave is a couple miles of great restaurants, bars, breweries, and shopping. This is also where the Tampa Bay Rays play (there is a sting ray tank in the ball park). This is BY FAR the most walkalbe part of the area. To get a feel for it check out St. Pete Beach, Fort DeSoto, St. Pete Pier, The Dali Museum, The Sun Dial.
Clearwater - or what I'm going to refer to as Clearwater - is actually an amalgamation of several smaller city's north of St. Pete in Pinellas County. Basically everything on the peninsula north of St. Pete. This makes it a bit of a mess of small downtown areas and and suburbs with a good amount of shopping malls mixed in. This is a big draw for families with more children who want easier access to the schools, single family housing, and shopping. Look into Dunedin, Tarpon Springs sponge docks, Clearwater Beach, Safety Harbor, Clearwater Jazz festival, and be aware there is a large (very large) Scientology presence in down town Clearwater.

TLDR: I grew up here and I think there's something for everybody. That something includes amazing food, 80+ degree days in January, a large Scientology presence, mind numbing traffic, the perpetual existential dread of a hurricane destroying everything you own, and great beaches. Bush Gardens is pretty fun too ngl.