What would be your recommendation relating to AdWords Quality Score: 1. Rather have many campaings with fewer keywords per each campaign? 2. Does it hurt to have non-performing keywords in some campaings? Should I remove them? Or is the quality score tied to certain keyword only?
No difference: One keyword do not affect another keyword QS so the number of keyword make no difference. Is the same: as one keyword do not affect another one you do not need to worry in removing low performing keyword. Avoid removing your keywords - use this as last resource - try decreasing bid, change ad or redirecting to a more relevant page if you have conversion problems with some keyword.
obviously you can remove the kewords which is not performing well. What is quality score? its all about clickthrough rate ,relavance of your adtext and historical perfomance of your keyword right . so what you can do is you can select a keyword which has got good click through rate you can start campaign based on those keywords instead of having too many campaigns with irrelavant keywords.