That sounds great! I think rasphberries are great in this situation, low cost to take care, and grow very quickly. Just trim to the size you want it, and each year, additional plants will grow from its roots. If you want some good sunflower seeds, at a low cost, I recomend Johnny's Selected Seeds (
http://www.johnnyseeds.com/), they have likr 1000 sunflower seeds for $6.00 last time I checked. Rashpberries grow well into the winter. Than for the spring time, I recomend strawberries, they grow very early spring to late spring, which takes care of that season.