Unpopular opinions, eh? I'm hip...
I am a malt-head (as opposed to a hophead). I like IPA just fine, but what I really love is all the lagers, Scottish ales, etc.
I can taste a nasty twang in your extract beer every time. If you must use extract, then partial mash is way better, and all-grain is best.
I don't think rye tastes spicy, not in the slightest. It's bready and a bit earthy, but no spice. Any spice is associated with caraway or choice of spicy hops.
Carapils is worthless. I've been saying this looooooooooooooong before the existence of the recent xBmt.
American commercial breweries just really don't know how to make good Marzens, or don't care. I think I might be done tasting American versions, life is too short and it just doesn't pay.
Almost every gose on the market is way too effing salty to be enjoyable. If you can taste the salt, you did it wrong.
Session IPA, Black IPA, Brown IPA, and Purple IPA are all terms that need not exist.
Homegrown hops are better for bittering than for flavor or aroma. Learn what your average alpha acid is through trial and error, like in the old days before the term "alpha acid" existed.
You don't need to rehydrate your dry yeast. It's one of the big advantages of dry. I know Denny agrees, but many do not, that's why I include this as an "unpopular" opinion.
Glass fermenters are better than plastic buckets. There, I said it, again. Glass is dangerous, yes. Do be very careful with your big heavy glass carboys. Fortunately, stainless would also be fine.
If you value your time and just want to get your brew day over with, then you are wasting a lot of time if you mash any longer than 40 minutes, and probably about the same for boil time as well. Could save some energy costs there too.
Step mashes are probably worthless. More experiments are a good idea but I'll probably not bother. When in doubt, just mash at 150 F for 40 minutes. You'll get very good beer with this mash "schedule". And...
If the temperature falls a few degrees during the mash, who cares. It'll be fine. I don't insulate.
It might not be worthwhile to chase high efficiency >85%. I finally ran one blind triangle efficiency experiment but need to run more as the results still were not very clear.
I only brew 1.7 gallons typically. There are numerous advantages to doing so. 5 gallons is too much for many people. I also brew on the stovetop, never did anything else and don't own a propane burner. I am ridiculed endlessly by my "friends" for being "the small batch on the stove guy". Whatever. Do what you like.
And... that about does it, for right now.