Fun 4: Humiliated by Burgundy, 7: Grasping at Straws and 9: Just Dropping In - These were updated from the first rating, and they're really solid easy-ish difficulty levels now.
Also Fun 4: Slow Motion - I didn't solve this last time. A tremendously fantastic level, simple layout but there's somehow quite a lot happening there. In my opinion this should be at least in the next rating, this is way too challenging for this place.
Also Fun 6: The Burrowers - Now a bit more reasonable solution in the updated version, this solution came to my mind at first but I think that the intended solutions works in a way that you dig few times with the hero climber lemming going that cycle from down to up again, so a shaft is created for builders to zig zag up it.
Also Fun 7: Health And Safety Gone Mad - This is an excellent level now!

Also Fun 8: Humble Bundle and 9: The Firing Squad - Really nice. The latter might be a backroute, though.
Hard But Still Fun 1: Uphill Struggle, 2: Lemming BBQ, 4: Pillars of the Community and 9: Increasing Productivity - Really enjoyable and superb levels now!

Hard But Still Fun 3: My First Crush - I didn't solve this the first time, got this now.

Hard But Still Fun 5: Master Exploder - A good level, could be a backroute though?
Hard But Still Fun 7: How's It Hanging? - This one I suspect backrouting almost in the same way as last time.
Hard But Still Fun 8: Tough Mudder - This level wasn't updated, and my solution feels ok even though it saves a skill. But you told me earlier that the only level I solved intendedly in this ranking was Spiral Staircase, so how it is?
Not Fun 3: Brickin' 'eck - Super awesome level, I'm really hyped about this pack!

Not Fun 5: Joint Construction - Few diggers saved, I'm suspecting a backroute here.
Not Fun 7: Offshore Rig - I used now my spare builder from my last solution to most probably backroute this again.
Not Fun 9: Rock Climbers - I didn't solve this last time, now I got it! Updating the top left area with a steel floor helped me to find this solution, and fortunately I saved my attempt replay earlier that helped me to set that difficult miner-builder thing up with that quick 55-75-55 RR adjustment. A hard and great level!