In Florida it's really hot. Even an A/C system in good shape may not blow super cold.
Check to make sure the heater / A/C door is closing all the way with a good seal. You could also do a heater core bypass to eliminate all engine heat from under the dash.
When converting to R-134, the total charge amount should be lower than it was for R-12. I think about 80%. Was the orifice tube changed? The stock GM one (white) works OK, but it's better to go with a smaller one like the standard Ford one, which is blue or green (I forget). I like the VOV better and have seen real improvement from it.
Airflow is also very critical. You don't cool the interior any more than you cool the condensor. Check your shrouds around the fan and between the condensor and radiator. Make sure all of the air has to go through the condensor. Sometimes you have to add some plastic or sheet metal to block off "sneak paths". Also check your fan clutch and make sure it is holding OK.
In Florida, running R-134 in an R-12 system, you should be running a high-pressure cut-out switch. Was the low side switch adjusted or replaced to match R-134 pressures?
I would only look into a new condensor after all of the other stuff has been looked into. I have good performance from mine with an old compressor. I use the VOV, added extra shrouding and switched to dual electric fans. The worst I ever see is about 95 degrees, though.