I don't frequent the East Europe section, as I don't have a particular interest in Eastern European hockey.
Russian U17 players are not better at this point and time. They have more potential and they're more talented in principle, but they're not actually better than 18-year-old Latvians. And it looks like you've missed that they have a Russian-based national development program now. Their U17 team doesn't have any North American players. Their U17 team consists of a mix of MHL/Russia U17 players. Their goaltending and D is worse, in terms of offense they might be a little better, but it's close.
We have played exhibition games previously against the Russian U17 (U18 vs. U17), U16 (U17 vs. U16) NTs, and beat them.
I have no idea why you brought up HK Riga. It's a single Latvian junior team, not our national team. Apart from goalies, we only have 6 MHL-based players on our roster and most of them aren't among our leading players.