Most modern HF rigs, including the FT-920, have an electronic keyer built-in, so you really only need a paddle.
In paddles, there are single lever and dual lever (iambic) types; and other than there being a thousand variations of those two basic designs, they're all the same.
I'd recommend a dual-lever paddle ("squeeze key") simply because you can use it either way, in an iambic mode or not, simply depending upon how you work it with your hand. A single-lever paddle won't work for iambic keying.
There's zillions of designs and some are better than others with regard to "feel," reliability, ergonomics and industrial design, but their functions are all identical. My personal preference, after using practically everything ever sold, is the simple Bencher paddle. Not expensive, easy to use right-handed or left-handed (just reverse the wire connections on the bottom), highly adjustable in every aspect, and heavy enough to "stay put" on the bench without sliding around. I have three of them, so I don't need to move a single paddle between different rigs.
There are definitely "connoisseurs" out there who prefer more elegant paddles, some of which cost hundreds of dollars each, but after trying most of them I still like the simple Bencher.
Of course, since a keyer paddle is nothing more than a pair of normally open switches, you can homebrew one, and that could be fun, too. Lots of published articles on that.
Good luck on the upgrade!