Glad you had some success JFR.
Your method is pretty much my method. A couple hundred here and there, then move around.
Funny story - I've been doing this steadily, at the same downtown casinos, for almost two years. I see the same personnel on a regular basis. By now you'd think they'd be on to what I'm doing, but there's a peculiar laziness among casino floor people that borders on apathy- they do their job and that's that. Unless you get chummy with them and as long you're not doing anything illegal, they'll leave you alone. You're just another humanoid paying the casino's bills.
I got proof of this one day when I brought a cupful of halves to the cage and gave them to a woman I see all the time. We started chatting about the crowd on Fremont St. (NASCAR was in town that weekend) and she said to me "Where are you from?"

This woman's cashed me out dozens of times but to her I was just another random guest.
So don't be nervous the next time you hunt the slots. Chances are the floor people have no clue.
Speaking of said slots, today had average results -
$40 in pennies got me eight wheaties (1942, 1945 (2), 1949-D, 1951-D (2), 1954-S, 1956-D) and three Canadians (1962, 1977, 1989).
$100 in quarters netted me my first 2008-D New Mexico but no silver.
$800 in halves got me a 1966, 1967 and a 1979-S SBA.