RK7: Stansted is fine. Of the London airports, it's the one I prefer. And Hahn obviously isn't a problem for you, though I would not recommend it for a day trip to somebody wanting to go to Frankfurt!
Actually, my wife and I took a weekend trip on Toytown Airlines, sorry, Ryanair a couple of weeks ago. We went to Aarhus in Denmark for GBP3 plus taxes and charges.
I have to say that with two exceptions, the experience was fine.
The exceptions? Avoid the in-flight catering. A cup of instant coffee costs GBP2. A small filled bap costs GBP4. So a bap and coffee for two cost GBP12, double the fare! OK, add it all up and it's no great problem, but it's still better to feed before you board.
Also, timekeeping can be dire. They try to blame delays on 'late arrival of the incoming aircraft' or some such. Sorry, what's that? It's all down to management, and perhaps they should admit that a 25 minute turnround at airports for maximum flying hours is just not a feasible business plan if customer satisfaction suffers.
It's unusual to get cheapo prices at weekends. Most offers avoid Fridays and Sundays. Last weekend, they had a promotion for Mon-Thurs flights at GBP9.99 each way including taxes and charges. Clearly, those inflight catring prices are important!
Oh, and they said they didn't have any credit card slips for inflight shopping on our outbound flight. Apparently, so many businesspeople are using FR that the cabin crew have to use the slips as receipts, even for cash purchases, so that the businesspeople can reclaim expenses. Hmmm ...