RE: Which Engine for Pattern
Daniel,
As others wrote, the need for a fuel pump is dependent on the plane you select, on the engine and on the placement of the fuel tank (if you have a choice).
If you stay with glow engines and choose a YS, you wouldn't need a fuel-pump. The same goes for pumped engines as such.
If the engine is not pumped and the fuel-tank is right behind the firewall, you might get away with not getting a pump, although large tanks and large engines tend to suffer, from attitude change induced fuel-pressure changes; compared to small engines and tanks.
If you locate the fuel tank on the C/G, there's no question about it... You will need a fuel-pump and regulator, even if you would just be 'ironing the surface of the sky'...