Please don't use GPool to stake Tfuel. Run an Elite Edge Node
Running an Elite Edge Node and staking your Tfuel there is VERY SIMPLE and helps out the network tremendously. Moderately decent computers (think 5 year old i5 desktop with a decent, wired internet connection) can more than handle an Edge Node and helps the network decentralize and become more robust. You can run it in the background and still use the computer with no problems.
If you're willing to stake Tfuel, then you really should consider running an edge node to help out your investment even more. I don't know/think there's anything wrong with staking Theta with Gpool, but you really shouldn't stake Tfuel with Gpool.