Dropped floats would definitely cause all of that. If it sat all winter without being started occasionally, and without the right amount of fuel stabilizer in it, then the gas in the line and bowl also could have evaporated leaving a bunch of yellowish crusty crud in the carb which could clog the needle and seat (flooding) as well as the jets and rods (poor idle and performance). Either way, probably needs a rebuild.

If it has brass floats shake them to see if you can hear fuel in them, if not use a pair of pliers to emerse them in water just off of boiling. The hot water will expand any air in the floats and cause bubbles to rise from any pin holes in them, which are usually in the solder between the two halves.