Dynasty startup trade/advice

Hey guys, I’m just getting into dynasty (first time ever) and I just got the veteran draft order (we’re doing a separate veteran and rookie draft). I have the 9th pick in the veteran draft, and I’m thinking about trying to trade some number of my rookie picks to get a veteran 3rd rounder. I’d love any thoughts or suggestions you all have. Is there anything I’m missing in my thought process? Should I be trying to trade into the top 4 of the 1st round with some combo of rookie/vet picks? Am I not valuing the rookie draft picks enough? Would a 1st&2nd rookie plus 5th veteran be enough for a 2nd round veteran pick?
Thanks guys