First, reduce the number of pending DownLoads...
What connection 'speed' do you have for Down and Up ?
The wise way to find your optimum configurations for the number of DownLoad and Upload slots is to start with the minimum and, with careful observation over a 'generous' period of time, increase the number of slots... SLOWLY... Step by step...
When things slow down in regards the total number of your transfer within a period of days, you know you have gone too far and you need to reduce, slightly, the number of slots allowed.
Same goes for whether you allow 'Browsing' or not and in regards to the maximum number of Queued Upload slots allowed.
Start Small... Increase Slowly... Share more with 'less'...
Most people are the same as you... They want the files to transfer as fast as possible and be DONE !
The only way to do that is for all people involved in p2p to use thier bandwidth properly so as to make for the fastest (shortest overall time) successful file transfer. Overall numbers of 'active' downloads/uploads mean nothing. Only completed transfers are important. The less 'clock time' involved means the less 'exposure' to possible failure.
Make any sense ?
btw... Frequent or overuse of the Force Resume or Search or Find More Sources functions will also slow not only you but the network as well...
It is considered very bad behaviour.