Hi Christoph, hi Qetuth,
it's funny that you discuss about this season being a good or a bad one. Definitely, it was a bad one due to the technical problems in the first Ts

And in fact, I don't really appreciate the boards of this season as well, so I would agree with Christoph.
But let me tell you some analysis I just checked out:
As far as I know, the random generation of T boards still follows the idea of the T pool, set up in 2006.
The pool of boards knows five categories: Small boards (A), big boards (B), long rectangles (C), low mine density (D), and other (E).
Yariv wrote in nonosweeper news: "Each season will contain 1 board from each category (=5 boards), 1 board from a random category and 2 randomly generated boards, so we should get a better mix of boards from now on!"
In S18, we had so far:
15x4/32 -> group C
30x10/180 -> group B
12x12/40 -> group D
8x8/32 -> group A (untypical one, but the limit for A is a maximum of 8 squares for rows and columns, regardless the mine density)
10x4/31 -> only fits in E
15x15/100 -> group D
In S17, there were the following boards:
7x7/15 -> A
30x/138 -> C
25x25/600 -> B
10x15/124 -> E
19x14/160 -> E
10x15/120 -> E
5x15/42 -> C
15x15/8 -> D
So, with two boards from group D (density lower than 50%), but both boards with a relatively
high low density, S18 is maybe a rather untypical season. However, S17 had only one board from group D, with an extremely
low low density. But that's the coincidence.
And non
otheless, there are still two boards remaining for season 18. I would prefer a really big board with extreme high or low density but who knows which board type will come....
I think the pool system really allows a better mix, but of course, we could still make categories more extreme to make sure that a higher amount of extreme board types is taken into account in each season. On the other hand, I prefer the current solution as there is a positive chance of having seasons without 12x12/45 type boards

Happy sweeping and a fair competition!