One specific criticism regarding Portugal-Iceland: main squad will not be exactly as considered there. E.g. Cristiano Ronaldo is considered a substitute.. Does it make a difference to your predictions?
You are correct about Portugal, not exactly the squad that will likely play against Iceland. We used the starting lineup of the last official game (I believe in this case it was Portugal vs England on June 2nd), which did not include e.g. Cristiano Ronaldo.
The actual lineup does impact the predictions - we will update the lineups before the start of each game, when the lineup is anounced.
In a future version, we would like to make it possible for visitors to change the players in the team, and automatically update the prediction.
I think the same is also true for Ireland. The last friendly match was used to view mainly fringe players. I guess 7/8 of the likely starters are here as substitutes. Perhaps you should look at the last competitive game in the qualifiers.
The actual lineup does impact the predictions - we will update the lineups before the start of each game, when the lineup is anounced.
In a future version, we would like to make it possible for visitors to change the players in the team, and automatically update the prediction.