I know I am a little late on this, but I have two different approaches for new seedings. Like most everyone here, I prefer to kill off the weeds a few weeks before doing the prepwork, it just plain makes it easier to work with. I also use a harley and a tiller, depending on the situation. I recently purchased a new 6 ft tiller for my larger tractor, I have had a 4ft model for years. My New tiller is a King Cutter and I like it a lot better than some of the higher priced brands. The KingCutter has 6 tiller tines on each row ( most only have 4) and cuts the soil very fine. The finished product is very smooth. So much so that I am adding a seedbox and cultipacker to the back of the tiller so I can till and seed in one pass. I will post a pic when I get it finished. If it works like I hope it will, I'll probably build one for my 4ft tiller and smaller tractor.
Harley rakes are a real pain if grass and weeds are present, they always leave a jumble of junk to hual off. Yes, they leave a very smooth surface, but the ground underneath is still hard and compacted. I am to the point now that if I am just smoothing and seeding, I will harley rake and then areovate to breakup the sub-surface and then seed. For those that are willing to pay for a quality job, I apply all amendments and till 6 inches deep and then Harleyrake and seed. Hopefully, my cultipacker/seedbox combo will help eleminate one step and provide a better product.