Khakis/chinos are fairly casual, pleats are a formal touch that should be reserved for 50+ year old men or a select few English suit styles.
Target's Ultimate Khakis are nice for the money (style, construction and fabric quality are all great for the price) - some of their non-ultimates fit a bit on the large side and have a longer than normal rise - unless you like having pants that zip up to your armpits.... In my experience most basic flat front khakis/chinos are pretty similar in look, very different in their fit. It's actually amazing how much variance there is for something that should be as predictable as sizing a pair of pants; vanity versus true sizing (is that 34" waist really a 36"?), manufacturing tolerances, fabric shrinkage allowances, pocket positioning and depth, length of rise, room for a proper ass vs. pants fit on a coke addict that gives you man-camel-toe, etc...
I'd generally consider chinos/khakis a step up from jeans but a little casual for the average professional work environment. Slacks are so much easier to maintain (little or no ironing - woot!) and a better match up with a blazer/sport coat in a pinch for a client visit or VIP meeting, etc..