When you say about swarms, some make it and some don't, are you talking about staying in your swarm traps or dying off?

If they aren't staying in your traps, put an open frame of brood in with them as soon as you see them in the trap. Any swarm I've caught, regardless of method, has stayed in the hive if I've placed a frame of open brood in with them.

If they stay and the numbers dwindle until they are gone, the swarm likely contained a virgin queen that did not successfully mate.

If you have early swarms still trying to fill their first nuc, they need to be requeened. It's not easy to requeen a hive with a caged queen until the hive has no resources to make a queen from. Remove the queen, wait 6 days, tear down all the queen cells. Shake every bee off every frame and double check to make sure you got anything that looks like a queen cell, then stick a caged queen in the next day, after you check for queen cells one more time. Poke a hole in the candy with a straightened paper clip and let them eat the candy to release the queen.

I'm a big fan of the Saskatraz queens. They're relatively cheap and readily available. A non productive beehive just takes up space. I use to keep them until they died out, just to keep my numbers up in case something happened to a queen. I finally started reading Micheal Palmers methods and started breaking up non productive hives into nucs and requeening them with good queen stock. Raising my own queens held me back for 4 years. I could raise them and raise quality looking queens, but I didn't have the drone pool that a queen breeder had so my queens never panned out, long term like the store bought queens did. Now many people will not agree with that and tell you they can raise better queens than a commercial breeder, but they're wrong. I could raise a better (larger) virgin queen than a commercial, but not having 10's of 1000's of drones saturating the breeding grounds meant mine weren't getting bred like they should.

If you do a fly back split this time of year, feed the piss out of them.

If my people, who are called by my name, will humble themselves and pray and seek my face and turn from their wicked ways, then will I hear from heaven and will forgive their sin and will heal their land. 2 Chronicles 7:14