accommodate their imperfections so they look good but do not minimize your technique.
become aware of their balance at all times because when they unbalance you it is because they are falling out of balance. If you can feel this happening then greater compression on your part is needed.
Reframe the dancing--heck if I can dance with those ladies and make them feel good then the easy to lead dancers are a snap. It then becomes a challenge rather than a chore.
Create situations whereby the lady has no doubt about your intentions: i.e. overstate the case.
I used to think that only when you can smoothly lead *any* partner through every step are you ready to move on, but that is wrong. If you are dancing to compete, then you need to be able to lead your competitive partner well. She may be (probably is) better than the average social dancer, and therefore does a better job with a worse lead. My partner and I agree that social dancing is the real test of your technique and proficiency, but just because I can't do a throwaway oversway with anyone on a social floor doesn't mean we shouldn't have that figure in a routine! When I was sticking to the "I want to lead anyone" attitude towards lessons, we weren't progressing very quickly as a partnership.

I think a leaders skill at a figure can be broken down into four levels:

basic understanding (can do with professional instructor)
understanding (can do with a good amateur partner who also knows the step)
good understanding (can do with an amateur partner who doesn't necessarily know the step but is a good dancer)
mastery (can do with virtually anyone)
Interestingly enough, I have had the most success with when dancing with non-dancers in Swing and V. Waltz. Swing has a sufficiently flexible hold to permit close control of what the lady is doing. Viennese waltz is so fast the lady doesn't have time to make a mistake. It's the slower dances, where the lady has time to think and to try to do something that she thinks is right (rather than moving naturally) that are tough to lead beginners through.

Mario Robau surprised me by telling me that he would happily give up his two US Open trophies to be able to dance well with any woman out on a dance floor. One of the most difficult skills in dancing is the ability to dance well with anyone. This not only requires being able to adapt your leading/following style to that of your partner, but also being able to adjust your repertoire of moves to your partner as well. Mario told me that when he dances with a woman for the first time, he leads her through "test" moves, easy moves that she can follow but which give away her following ability. Afterwards, he selects only those moves which he knows she will be able to follow. A woman who is a beginner need never fear dancing with Mario; he will always make her look good (and himself as well).

One of the most common leader mistakes is trying to lead a less experienced follower through complex moves. Intermediate and advanced dancers should start simply and work up to more complicated moves as the tenderfoot follower is ready. When you show off the nifty move you learned at the last workshop, and the follower can't cope, you both look terrible... when you do simpler moves with elegance and confidence, and the follower is happy and on the beat, you both look fabulous. If the follower loses the beat on an underarm turn, it is very likely that she will be lost on the subsequent pattern, so make sure she is on the right foot before you continue.