1. Radek lost someone very important during the Velvet Revolution. They didn’t die or anything (as it was a fairly bloodless upraising), but he lost them nevertheless, as painfully and irrevocably as if they had.
2. Radek actually speaks and understands English perfectly. Also Russian and German, and lately he’s been taking Japanese lessons from Miko. He retains his accent for a variety of reasons, not all of them clear to even himself. At first it was a bit of an in-joke for the crowd of one, and yeah sure, he knows that the ladies like it and he can usually score an extra pastry with his tea (no, he doesn’t drink coffee) from Marisa at the kitchens. The accent is an excuse, a protection, a permission, a way to stand out or to hide. It’s also a reminder, both to himself and to others, that being different isn’t always a bad thing. Out here, surrounded by Wraith and Replicators and Genii and thousand other hostile races, it can be difficult to remember that sometimes.
3. It’s true that Radek is the person to talk to about scoring some liquor in Atlantis, and it’s even true that he designed and started the distillery that operates in the level 9 biology lab C (the botanists are now running it themselves though, with some unexpected help from the two SAS guys with matching tattoos). Radek himself, however, only drinks very little and only occasionally. There was a period in his life, not long before he got recruited to the base in Antarctica, when he teetered on the edge of becoming a full-blown alcoholic, and it’s not something he is keen to revisit.
Nowadays he let’s go in other ways.