because the way training works (being able to train Speed/Agi together), if your going to cap first, you need to cap both, not do Agility and Strength, because then you're left training Speed and I don't even know what...Tackling?
Strength right now (who knows what'll be next season) is useless for DEs.
If you want a ridiculous Speed/Agility guy at DE, you missed that boat.
If you just want to continue this player, train Speed/Stamina until Speed is 30, save up SP and softcap it. And get Agility to 60 asap.
Long term goal, keep pumping both speed and agility until it costs 4 SP to raise 1 point.