Not very soiled, Chemspec Prekleen Enzyme soil lifter
Medium soiling, Kleenrite Extreme, still safe for new carpet.
Heavy soiling, Prochem Ultrapac Extreme. However I might look for an alternative that doesn't have D-limonene. I'm messy with my chemicals in that I get them on my hands regularly and don't wash it off, rather not have that stuff giving me cancer.
Additives are a couple OZs of Newline Pure Citrus if it's a real oily or greasy situation or a scoop of CTI OSR if I feel like I need some peroxide to brighten up food stains.
Favorite deodorizer was CTI Odor Eliminator but they recently changed the scent and I don't care for it now at all. Need to find a replacement. Hyrdamaster Multiphase is a good one but it's a bit foamy so I'm not a huge fan, I hate cutting down on my suction. Fresh Wave IAQ is decent but I find the dilution I have to use to really notice results is about 3-5x compared to the 2-3ozs per hydroforce of Odor Eliminator I used to use.
Upholstery: no product has come close for me to being as good as Workmaster Neutrasolv. Neutral PH, works well on all fabric types including natural fibers, great on rug fringe too although it causes bleeding a bit more easily than some other cleaners so pretest first. 6:1 dilution is fantastic for a liquid upholstery prespray, lots of them are straight or 1:1.
Urine: 99% of the time CTI OS-1 or OSR. OS-1 is way more expensive but it works so well on smaller spots that are hard to keep track of after the carpet is wet. Almost never have to come back to retreat a stain when using that stuff. I really like Unleashed Un-Duz-It since it isn't peroxide based, just that much less a chance you bleach something but there is no way I will wait 1 hour dwell time for a product. I use it for wool rugs back at the shop and it's what I recommend to clients that get puppies and want to semi-maintain the puppy spots themselves in between cleanings.
Encap (99% of the time with a CRB, 1% with a 175): Shaw Total Care Stain and Soil Remover. Really not sure if it works any better than the CTI APE line. I might pick up some Whitaker encap again (its been like 7 years) and recompare results.
Wool rugs: Chemspec Oriental Rug Shampoo or if it's very die stable Carolyn X-tol works a bit better but is a higher pH.