Now, there are better Android phones out (mainly the S3 and S4), but my S2 still serves me quite well. In fact, I haven't found anything that it won't do. So there's no need for a new phone, and there is no need to continue on my expensive contract.
So I went sim-only. I ordered a sim with a company that a colleague gave good reviews to. Now I will get 100 call minutes (or 100 SMS) and 1000 MB internet connectivity per month for only EUR 13. That totally works for me.
Also, we have a fibre-optic cable dangling in our garden. On August 21st, it will be connected inside our home. I'm looking forward to 100/100 internet speeds.