RhinoFish - 8:06 pm on Jan 8, 2013 (gmt 0)
New bidders, position, bid, price competition, auto-targets, negative keywords, promotional ad text, image quality, trusted store status... you need someone to look at all the details here, the relatively superficial inquiry here, imo, leaves too many things out.
Google's morphing the relevance over time, including bid and brand strength and more. Take a high volume, high CTR Ad Group and do some bid experiments, to see what the bid-volume control ratios looks like, then wrap lessons learned into other auto-targeted Ad Groups.
You should be, over time, lowering the bid for your "all products" Ad Group, as you gain bid / volume / reach / ROAS control over all of your other (not all-products) segmented Ad Groups. If the targeting and bid overlap between your "all products" and specific Ad Groups is significant, your bid controls can be squishy. Make sure your Auto Targeting method of choice has relatively little overlap (where you need bid segmentation), or squishification will fungibilify your efforts.
I'm thinking what I just said would make sense to like 7 people, and 2 of them are my biz partners. Sorry. :-)