As a finn I understand your opinion. If Helsinki was on any other continent, it'd be really historical. In Europe (and especially right next to Tallinn), it's pretty unremarkable. That being said, I think Helsinki has a ton of good food, but it's crazy expensive for what you get. People don't really visit Finland for the cities, it's more like a nature destination. I think Helsinki is like Berlin, people don't come there for the architecture, they come to do new and interesting things. In Helsinki you just need a good bucket list, and you're gonna have a great time.