I think a visa to Russia is obligatory even these days. Tallinn is different as Estonia is part of the EU and the Schengen area, but for non-EU citizens different rules might apply. Check before making any reservations... It seems that the airport strikes are over for the time being and even the weather seems hopefully slightly springy for next week!
For Helsinki sightseeing, I personally would recommoned Suomenlinna (the fortress islands in front of Helsinki, a UNESCO World Heritage Site) for a visit on a good day: 20 min ferry ride from the Market Square (Kauppatori, part of the normal Helsinki public transportation ticket system). Beautiful views and a great late 18th century milieu, ok restaurants also available. Finland 100 year continues and at the Design museum a new exhibition opens on Saturday displaying one object for every year of the Finnish independence (Korkeavuorenkatu 52). Also, the new permanent exhibition on Finnish prehistory will open on Saturday April 1 at the National Museum (Mannerheimintie 34, right next to the Parliament). Also, apparently everybody (but NOT me!) loves the new Helsinki City Museum (Aleksanterinkatu 16), but it is worth a visit (I guess

) An exhibition of smells of Helsinki going on at the mo.
If you are not afraid of nudity and communal bathing, try the Kotiharju sauna at Kallio (Harjutorinkatu 1, open 2-8 pm Mon-Sat, 13 eur, you can rent a towel, buy a pefletti [seat cover] and drinks), it is the one of the few public saunas remining in Helsinki (the wood heated stove is just wonderful). Also, the baths at Yrjönkatu are great, especially if the 2nd floor is open (
http://www.hel.fi/www/helsinki/en/culture/sports/indoor/swimming/yrjonkatu-swimming-hall).
It is funny to be travelling to my "home" competition as a tourist (I live abroad at the mo), but I will actually try and catch the new exhibitions and I'd love to make it to a proper Finnish sauna (but is is difficult with the comp schedule and all the other activities I have lined up so far).
At Salve, have the fried Baltic herrings and mashed potatoes! It's a classic! Cannot be there that day, but hope you all will have fun!
E