Old school one piece guy here as well. My preference for over a decade was the OG Miken Freak and Freak 98’s, so I lean more balanced/.5 ounce endload swing weights.
The suggestions above are good and you have to acknowledge at the start trying to find these in great shape is like trying to find a unicorn.
I really like the Bombardier LC. I have a fresh one without many swings on it. It feels really good but it’s not on par with a well-used “clacking” Bombardier. Hence, there is still work to be done. This is the closest thing I’ve found to the OG Freak feel but with the right technology for the ASA 52/300 balls. It’s far from exactly like the OG Freak but it’s similar enough to me at a time where almost everything else feels vastly different. I hate handle flex and my Bomb has the 2500 flex handle. I would rather have the stiff handle but the flex handle on the one-piece design is still nicely rigid.
I was also able to pick up an Anarchy “No Name” that’s in great shape. The weighting and feel is good, but it’s going to take some BP and hard balls to really hit gamer status. This has a mid-loaded feel and the handle is stiff.
I’ve toyed around with the Adversity. If you don’t want to put any swings on a bat and get good performance with a mush ball, this may work for you. There’s a ton of barrel flex on there and it just feels too soft to me. Had one with a 2500 handle and the entire bat was squishy feeling at contact — hated it but it performed well. I now have one with a 4500 handle that feels a little less squishy but the jury is still out.
Finally, some additional info that might be worthwhile. I figured I would never find a 2-piece bat I could stand to use. What I’ve learned is that there are a few I like but it’s heavily contingent on the handle stiffness. Picked up a well-used older 27 ounce Torch LC with the extra stiff handle and it is straight fire. Another option is the Boombah Boss T3 Compressor line — the XRT handles on these is nice and firm and it feels solid through contact.