I have written an ebook about games. The emphasis is on card games and Finnish games, but also board games including abstract games can be found. The book is in English, and it can be downloaded on my otherwise Finnish language website http://fiktio.wikidot.com Just select My games on the PDF menu.
When you said "Finnish games", I thought, "ooooh, Skruuvi!"
You see, Skruuvi sounds like a great game, but I tried reading the rules from a few different sources, and I can never wrap my head around the bidding conventions. Your text seems a bit clearer than the others, but not enough, I'm afraid. What does first-round suit mean? And second-round suit? A "Skruuvi bidding for dummies" section would be very much appreciated.
It sure doesn't help that I'm a noob when it comes to trick-taking games, but other, very experienced folks seem to be having trouble too.
Other than that, there is a LOT of content there! I'm curious to read about all those other card games.
First-round suit is defined in the first paragraph of the bidding conventions chapter. Whether there are card exchange conventions depends on the players. In some circles they are used, in other circles banned.
First-round suit is a suit that is strong enough to be bid on the first round of bidding. Similarly second-round suit is a suit that is strong enough to be bid on the second round of bidding.