OK...hold on here. The carbon/propane based refrigerants are no more flammable than any of the environmentally UNSAFE freons on the market. That's hype by the oldtimers and freon sellers. I've been using the alternatives for over 25 years in over a dozen different vehicles. I've read all the industry standard sheets and was involved in legislation protecting the consumer's rights to use the alternatives for many years. They are lighter, more effiicient, create less pressure in the compressor, and have no negative environmental effects. There has NEVER been a documented incident of fire or explosion due to alternative refrigerants.
That said, I wouldn't start a system with a mix of Freeze 12 and R-134a. Even though they are mixable aith no negative consequences, it's better to go with one or the other. Since Freeze 12 is just the gas, and not the oil charge itself, I don't know why a new compressor would have it labeled as being in it. Even if Freeze 12 was used prior to rebuilding or replacing the compressor it wouldn't affect the compressor since the alternative refrigerants can all be used with any of the oils. I use Enviro-Safe myself, and have for at least 10 years with great cooling and no problems whatsoever.
But you're problem seems more like circulation of the refrigerant. First, your -24hg of vacuum when you evacuated th esystem was not enough. It needs to hold at -30 for at least 30 minutes (2 hours is a better test) with the pump OFF. If it doesn't get to -30 there is a leak or partial blockage somewhere. After you get it to hold at -30 you can add your refrigerant and cycle it back into the system. And, yes, 30+- at 2000-2500 rpms is good. You should have plenty of cold air at the vents. However, if your ambient temp is 100+ you will not get 40 degree vent air. 60 would actually be pretty good. I think the rule of thumb used to be ambient minus 30-40 at best. If your burb is a dark color like mine it takes twice as long to cool down.
Your compressor oil is a different problem, too. I know you don't want to start over, but you need to know exactly how much oil you have in there. If you got no oil out of the drier that's not a good sign. Obviously, you need to ad back the recommended amount. Most rebuilt comps have some oil in them. You can dump it and see how much comes out until it's empty. I think you have to turn the vanes to make sure you get it all, but turning them backward can damage the compressor. If you start from "0" it's a lot easier than guessing. Apparently, our compressors have a history of losing their oil and rattling themselves to death....and too much oil makes the system work like crap.
If your compressor has a warranty you might want to take it back and get another one. I know it's a PITA, but what you have now isn't doing the job...and you don't really know what is in your system. I've replaced compressors and had the "new" one self-destruct almost immediately (using R-134 or R12 or any other). Remember where they are rebuilt. Make sure your valves on top are not leaking --- another common problem.