New to suspension - Leaf spring install

My situation last year was very similar to yours - I had tired rear leafs, reasonably new 4600's in the rear (no point replacing) and Replaced my leafs with General Springs HD - I'm quite happy so far. I drive with a cap that I use as a gear closet/tool shed, so I reliably have a fair bit of weight in the back.

My 4600s handle the springs just fine, The springs definitely gave a lift at first and rode stiff for a month or so, and now a year later they have sagged to be nicely stock height. They ride well and hold weight well. I'd say go for it.
At the same time, I also replaced my front shocks with 4600s and new Moog springs which also gave a mild "lift" at first, but sag to be stock height - or thereabouts.