Being a seller and a struggling one I think the main thing with the orders and the ranking is the research and keeping in touch with the changing algorithm and keywords. I take a couple of weeks but you get the hang of it. once you do, it's pretty much the same.
I'm sure you're familiar with the keyword research method. Not very mainstream but still I think without seller plus, it's the only way, or at least that I know of.
Search the main keyword in your niche and go for the gig with the lowest number of reviews but still in the top numbers or the pages and notice the description and keyword difference even the tags. check out a couple of gigs and choose common keywords and check out the gig volume in those keywords as well. as I said once you get the hang of it it's pretty easy.
And once you get some orders in...... then the real magic begins to happen.
I hope you already know this and if you don't, I hope this helps.