Some windsurfers just don't like the big boards and sails (cost can be an issue), even though they would get more planing time. It's an individual thing. I would rather be planing on my formula board in 6-12 knots rather than sitting at home or on the beach waiting for more wind. Some will venture out on their intermediate size boards and sails and slog, plane, slog, slog, plane, etc
And yes, the range of equipment options is mind boggling. I actually think it makes it more difficult for beginners and intermediates to get started because it's so difficult to know what will be best for them.
When I started in 1984, there were a half dozen long boards to choose from and all were similar in design and performance. After mastering the long board, then there were a half dozen "transition" boards where one could still uphaul and learn the basics of the short board. Then there were a few small board options after that. It was pretty hard to make a mistake in a board selection other than trying something too small too soon.
You may be better off staying with your gear for a while longer and then decide what to do. The Futura 141 may be a good option if you don't want to go to the really big stuff, but it's a little close to your 130 liter board. A good combination for your size would be the 141 and then something around 100 - 110 liters.
I jump from my formula board down to an iSonic 111. The sails I use are - formula board 11.0, 9.2 and sometimes 8.4. Then my iS with 8.4, 7.6, 6.6. Next is my bump and jump 105 board with 6.6, 6.0, 5.2, and 4.5.
Formula 160; iSonic 111; HiFly Move 105; Tiga 263; '85 Mistral Superlight.
Maui Sails TR 11.0; 9.2; 8.4; 7.6; 6.6; Maui Sails Switch 6.0; 5.2; Maui Sails Global 4.5; 4.0.