Welcome to what I call the "true" quilting.
Handquilting thread works the best as it is stiffer and holds up well to be dragged through the fabric repeatedly. Use cuts of no more than 18" and it is always single thread. If you want to hide your stitches as much as possible use colors to match each section of the quilt you are working on. The only problem with that is unless you have a overall printed back it will show there a lot. I have been handquilting for at least 40 years. The first five at least I did stab and stitch. I then advanced to two stitches at a time. Now I probably average at least three stitches on one needle. A lot depends on the density of the fabric, the size of your needle and the thickness and density of the batting you are using. For my best work I use cotton batting at the "request" thickness which is very thin. The nice thing about today's battings is that they make it possible to quilt without having to do it extremely heavily unless you so desire. Make sure you read the label. If it says you can quilt as much as 4" apart you can be sure that your batting will stay put after being laundered.
If you are planning on using a traditional quilting frame that is stationary it would be to your advantage to learn to quilt with both hands. Since I touch type and play the piano it didn't take me long to perfect using both hands. It saves a lot of contortions when using a stationary frame. It also makes it easier for me to spend lots of time quilting without destroying my neck. After 40 years I have carpal tunnel problems with both hands.
I find handquilting very relaxing. I have discovered the "continious" line quilting stencils that were designed for machine quilting. They make handquilting much easier as they prevent having to stop and start so much.
Good luck and have fun.