A full listing of Boltinoff's features would probably fill a small phone book. Wikipedia lists the following:
Abdul the Fire Eater, Bebe, Billy, Buck Skinner, Cap's Hobby Center, Cap's Hobby Hints, Casey the Cop, Charlie Cannonball, Chief Hot Foot, Cora the Carhop, Dexter, Doctor Floogle, Doctor Rocket, Dover & Clover, Elvin, Freddie the Frogman, Hamid the Hypnotist, Homer, Honey in Hollywood, Hy the Spy, Hy Wire, Jail Jests, Jerry the Jitterbug, King Kale, Lefty Looie, Lem 'n' Lime, Lionel and His Lions, Little Pete, Little Pocahontas, Lucky, The Magic Genie, Moolah the Mystic, No-Chance Charley, Ollie, On the Set, Peter Puptent, Prehistoric Fun, Shorty, Stan, Super-Turtle, Warden Willis
Just at a glance I could add Peg and Varsity Vic to that list and I'm sure there are dozens of others. Some of the strips were already anachronisms by the 1960s; the jitterbug was a swing dance craze of the 1930s and 1940s, and carhops were waitresses employed by fast-food joints of the 1950s. They had mostly disappeared by the time I was a kid. A carhop was featured in the opening sequence to Happy Days, dumping a meal on a couple of cops (starts about 1:10):
Dover and Clover were significant in that they were probably Boltinoff's only work to appear on the cover of a DC title:
Dover and Clover were twins and inept detectives. They appeared on the cover of about 10 issues of More Fun Comics in the 1940s.
There does not appear to be a strong correlation between the features Boltinoff drew and the comics in which they appeared. Don Markstein notes:
They were mixed randomly, with "On the Planet Og" sometimes turning up in Tomahawk and sometimes in Tales of the Unexpected and "Hy Wire" sometimes in Strange Adventures and sometimes in Superman. The only certainty was that practically every DC comic book would contain something by Henry Boltinoff.
On the other hand, there was some reasonable consistency; Batman usually had crime-oriented Boltinoff strips like Casey the Cop, Lefty Louie or Warden Willis, and Super-Turtle mostly popped up in the Superman family of magazines. Here's Homer doing some spelunking in one of the Cave Carson Showcase issues I mentioned a week or so ago:
The strips were generally 1/2 to a full page long, although in the 1950s and early 1960s there were a few two-pagers. Here's Varsity Vic from Adventure #300:
Here's Peter Puptent from Doom Patrol #99:
Around late 1965 to early 1966, most of the Boltinoff strips were discontinued. They were replaced with Cap's Hobby Center, shown here from Doom Patrol #100:
The obvious intent of the Cap's strips was to cross-sell some of the DC advertisers; model-building kits were very commonly featured in the magazines. The products were even mentioned by brand in a few cases:
This of course refers to the Revell Space Capsule giveaway covered by Mark Engblom a few years back.
Cap's Hobby Center gave way to Cap's Hobby Hints, where readers could send in their suggestions and win $5 and the original artwork from Boltinoff. These frequently had to do with model-building:
Boltinoff went on to even greater fame and fortune when he created Hocus Focus, a two-panel cartoon strip that was syndicated in hundreds of newspapers. Readers looked at two very similar drawings and had to find the six tiny details which differed:
In that one, you can see that the kid's baseball cap is reversed, the hole in the window is higher, the table has a drawer, the lamp is added, the ball is missing, and a piece of glass (by the man's right foot) is missing. Incidentally, the bar-top game machines in many establishments these days have a version of Hocus Focus, but with photographs instead of drawings.
Mike's Amazing World of DC Comics has a huge Boltinoff gallery.