The biggest thing for me as a decathlete was knowing my strengths and my weaknesses. Right now your strength is speed. That is one of the greatest strengths for a decathlete to have, all the other events will fuel off of it. It seems as though right now, you have a lot of weaknesses, but you need to rate your events from the worst to the best. Your event that you feel needs the most time, is the event you want to touch upon more often. I know for me, it was javelin. I wouldn’t neccessarily throw the javelin every other day, but I would get out there and throw weighted tennis balls 3 times a week to gain flexibility and strength.
Another approach since you are still early in your career is to take one event a week. Now, this does not mean to drop all other events or your other training, but to incorporate that event almost everyday. I was having a lot of trouble with discus my junior year, so I decided to really become proactive with it. I made sure for one week I physically and mentally prepared for the event everyday. I threw it three times that week, but I also would mentally go threw the motions all the time.
The trick is to not overdue it, but to get just enough that you become accustomed to the event.
Also, if you want to be a legite decathlete, get yourself a good book on track and field. I suggest Tom Ecker’s Basic Track and Field Biomechanics. The more you understand about the events, the better you will be in the end.