I have it that way. It still tries to connect over 800 relays. I can't see an option to only use 3 or 5. It keeps trying to connect all those hundreds.
Discussion
If those are under "connected relays" and not the other relay sections iirc those relays were automatically added there because they are needed to get content from people you've followed.
Those 800 are basically just 1 connection for your device thanks to Tor. But I'm not sure how you can solve it beyond that, there might be a way