Your build's not really good, but it's not horrible either. Some suggestions I'd make are to move your equipment into stamina, take strength then speed to the second caps while training agility and stamina. Once you have strength and speed at 60 raw start saving your SP until you can cap agility in one step (getting the most out of your training), then start training stamina and carrying. Your stamina should be in the mid 20's by then and you can move your equip to a major (speed or strength, preferably).
If you sign to a real team before you can accomplish these things then you may need to adjust and get carrying higher. Fumbles don't matter if you're in d-league, only setting up your build for success matters.