First off, start anywhere except the UK for a DONEx RTW. Highest price (ok Ireland may be higher), lots of UK taxes, and plenty of BA fuel fines. You can check the sticky's for the best place to start in Europe, currently Switzerland and Sweden(I think).

The routing is fine, but you have used only 12 of 20 segments with some very short segments as well. Many are less than 2000 miles so you would get the lower tier points.

You need to tell us if those are places that you want/must visit or if you want to fly more segments for more tier points.