Hallgrimsson was also heartened by his substitutes with Jack Taylor coming closest to scoring on his international debut after replacing Evan Ferguson.
Taylor’s impact followed Festy Ebosele coming off the bench to set up Robbie Brady’s winner in Helsinki.
“Both this game and last game, the guys who came in [off the bench] proved a point that they want to play and be in the team,” said Hallgrimsson.
“Again, some positives to take away, maybe a lot of positives to take away from this game, but you never want to lose 2-0.”
The Icelander added: “It’s a good team, good players with maybe too little belief to go into games like this. At this level you need to have your chest forward when you play games.
“You have to be on the front foot, and it seems we need moments to get that, to concede in the last two games to start playing as we know we can.
“There is belief in this team for sure, I have belief in these guys, and I hope that people have seen that this team can be really, really good on their day.”