Upgrade Reccomendation (GL-MT300N-V2)

Hello there
I have a Mango currently, and noticed that my load averages are high for a single core CPU (often jumping up to 3.67, 2.05, 1.77 and higher). It’s because I’m using it as my main router, likely.

Can someone reccomend a different model that can handle being used a home router (higher power)?
It needs to have a USB Port I can use for Tethering, but not be too expensive, please.

I’m within the return period still for the Mango - I brought it as an experiment!

(Currency GBP, If it helps)