While I think the heat treat is the most important aspect of any knife steel, I do have some current favorite steels.
D2 - discovered by accident when purchasing a Queen sodbuster. I loved it from the first. Easy to sharpen, holds a fine edge very well, and is very rust resistant. Since I always carry a traditional (as well as a "work" knife) this is a favorite now. It is affordable, touches up well, and is a very solid performer. I have D2 bladed Ontario knives, Kershaw knives and Queen knives. Like them all.
8cr13mov/AUS8 - I can hear the gasps of despair from here! I bought a larger work knife (I am in construction) to do daily, ugly chore I didn't want to use a less robustly built, more expensive knife to do. I bought a RAT1 after a lot of conversation here on BF. The AUS8 was pretty soft, but even after it lost its razor edge it kept cutting. Both steels are easy to touch up (on sandpaper if needed!), don't rust easily, and make a completely affordable work knife blade. After cutting a couple of shingles, some sheetrock, scraping some caulk or whatever task comes along I can clean up my knives with either of the steels and put a fresh edge on in a literal minute, and it is back to work. Replacement of this type of knife is affordable, too. Since they aren't an arm and a leg to buy, I am not afraid to really put them to work. My RAT1 (AUS8) and my Kershaw Tremor (8cr13mov) are my favorite clip on workers
I have S110V, 154cm, 12nc27, VG10, AUS6, and a couple of others. All are good steels when matched to the right knife design, none would I see out because I like the steel so much I had to have more of it. The two stand outs would be the AUS6 that has come my way on a couple of Remington branded Pacific Rim traditionally patterned knives and the VG10. The AUS6 is as good as any steel I have ever had in a traditional pocket knife, and better than most. The VG10 is on a Kershaw "Crosslock", and it is superb. It is ground flat and thin, and it takes an edge that is very fine and holds it a very long time. To get it back to a razor, a few passes on a strop loaded with green compound and you are back in business.
I rarely carry carbon anymore. Although I have about 30-40 carbon bladed knives I have collected over the last 50 years, I don't miss rust prevention and soft steels at all.
Robert