Went down last year...would recommend going later in March as weather would be better...but I went for the last two weeks and it was pretty windy and cold.
Flew to Tampa and rented car (cheap) and stayed out in Clearwater Beach (good deals on hotwire) about 20 mins to Dunedin and other complexes and much better nightlife than Dunedin/airport; Phillies/Yankees ST sites are also close by.
Need to look at different spots for tickets if you want deals, depending on the game you can get them cheaper on stubhub or other aftermarket sites that the Jays Team site. (Lots of season tickets holders just trying to recoup a few bucks). Bought 5 premium seats for the last ST game at Dunedin for 8 bucks each. But depends on who is playing, lots of teams have loyal fans who travel around with the more popular teams (Yanks, Sox, Phillies, game tix will get scooped up fast)