I had a flash yesterday on how to implement a solitaire racing game.
The first solution would be a kind of beat your time mechanism like rally man. But it's not that interesting.
The second solution would be to have a mix of super off road and Stunts PC game where you have a racing track with various stunts that you need to perform. The goal is to survive. Reach the end of the track without crashing.
There would be some metrics to keep track every turn like speed, grip, damage to the car, etc. The idea is to make sure the same stunt will not get cough at the same speed, control, etc. Where could be water that wet your tire changing how you car behave on the road.
Else I was thinking of using arena maximum card system, or something similar, to prevent optimal solutions and to have a replay-ability value of the same track. I would give each card 2 purpose to get a more interesting strategy.
A GTA board game would be more like an adventure questing sandbox game where you wander around the city completing objectives or causing trouble.
I had on my list a crime fighting city game where you wander around and investigate. It creates the same issues as my Arkham horror steam punk games. You cannot have a real investigation as a board game. You can only have a game where you put out fires. The "Kick ass" board game could fit into that category.
This open world concept is expandable to GTA or Just Cause as a board game. The classic fantasy RPG adventuring, like Rune Bound, could be used for both those themes.
Hmm! I wonder if Rune Bound could be rethemed/redesigned to Just Cause. I like the idea behind Just Cause, I am just not skilled enough to play it as a video game. With Rune Bound, you are completely abstracting the encounter system. It's not always easy to do, I had an hard time coming up with such system for my steam punk investigation game. I ended up with my 2 rolls success + casualties system. Not sure if it actually worked well.
Else a putting out fire system like Arkham horror 2nd edition could be solid. AH 2nd ed is indirectly a dungeon crawler inside a city, but there is enough details to make it implementable as a board game.
The theme implies a strategic and tactical layer. But as a board game, you cannot have both. As a video game you could pause the high level strategic layer and resolve combat as a tactical layer. A bit like Empire of Sin and other NES koei games.
In a nut shell, detailed combat are easy and fun to resolve, but works only well in a tactical game from a thematic perspective. If you try to abstract detailed combat, you can focus on the big picture, but it's hard and less fun to abstract combat.
Anyways, I'll stop talking, I am diverging too much.