That's a really nice progression you've had. Props on moving from being a distance runner to a sprinter...not the usual direction you see people take.
I have a multievents background, but the general principle I've seen work for a lot of people is based around three types of workouts, of which you do about one-two of each every week depending on where you are in the season. The workouts are extensive, intensive, and speed. Extensive is above 800m pace / shorter recovery, intensive around/above 400 race pace / longer recovery, and speed is 95%+ w/ full recovery. Over the course of the season, you want your extensive to go from longer and slower to shorter and faster (400s,300s,200s), and your intensive to go from shorter to longer but maintaining speed (100s,150s,200s).
Early in the season, one or twice a week of 30 min plus easy cardio will help you build the strenght to manage hard workouts later in the season. During your competitive season, you can replace some of the extensive workouts with speed endurance (ie. 3*300 at just under 400 race pace with full recovery), but these should be early in the week.
I also think that explosive lifting (snatch, power clean) and ploymetrics (both bonding and boxes) are essential for building dynamic power. Doing speed session on moderate incline is great for improving hip strength and knee drive.
This probably all seems very obvious, but I think it's a good structure to base workouts on, and gives you flexibility to pick challenging and interesting workouts that work best for you.