...how long have you been paddling? That's not meant to be condescending, it's just that if you haven't been at it long, there's no point in stressing over the design of your paddle blades, as your preferences are probably not well developed and will likely change over time. Just build something that interests you and try it out. Experiment to your heart's content. Building paddles is inexpensive compared to buying them, so you don't have to restrict yourself as much. Go nuts and have fun with it. Build a Euro, a GP, an Aleut, a wing or whatever interests you.