For general note taking and journaling, I prefer a Rhodia Webbie which have replaced my old general-purpose, government-issue steno pads. I am used to the old 6x8 steno pads, and find the Webbies are very similarly sized, but with vastly superior paper that I do not need to dump several dollars worth of Washi tape, glue, and PostIt Notes to make work.
For notes that I am going to rip the pages out and stick in one of my binders, I prefer A5 sized paper. I just do not use a B5-sized notepad very much. I do use quite a few 3x5 notepads. In the Rangers, we used Rite in the Rain pads almost exclusively. Now that I am retired, I have fallen in love with the refillable Lihit Lab pads. Thankfully, the Lihit Lab pads fit into my old Rite in the Rain nylon covers.
I still use several Rite in the Rain zipper-closure nylon covers for notepads and small journals. Might give them a look for covers as well. I use quite a few of the Rite in the Rain 7x5 and 6x9 nylon covers for my notebooks and steno pads.