Returns and Cyclic charts.
As noted, Return charts for Mercury and Venus to themselves don't seem to have a clear picture of what the cycle would represent and how it would be used.
Mars Returns are also 'iffy' in nature -- sometimes Mars moves fast enough to provide a reasonable Ascendant, at other times not. That would make house interpretation useless and only the current and unfolding aspects to Mars would be useful. In essence, you are just as well off using a transit chart. The same problems exist with Return charts for Jupiter, Saturn or the others lying far out in our solar system.
Cycle charts, using the synodic cycle are another thing. However, Moon-to-Sun doesn't do much for the individual. What might be useful is transiting Moon relative to transiting Sun with the natal angle used to define Moon-to-phase-angle-Sun. This is a blend of a Return chart and a Synodic chart. I had studied these 'Pattern" charts for a couple of years some three or more decades ago. At that time I couldn't find a reliable use for them. Of course I wasn't as conversant with Returns and Cyclic charts then as I am now. Also, I have computer assistance now to improve their timing and accuracy.
Jupiter-Saturn cycles have long been seen as business oriented. I call them, for personal use, the business-of-life planets. Again, the changes in relationship are slow and best seen and used as development, trending, influencing effects, IMHO.
If one wants to have fun with Return charts, then Moon-to-Sun, Moon-to-Mercury, Moon-to-any planet Returns are fruitful. The Moon portrays the changes that come into one's life, the natal planet is the adjult, adapted expression of that planet that we have come to express. It is no longer 'potential.'
** t/Moon-to-n/Mercury portrays how we deal with news, opinions, communication issues, writing, documents and agreements. I used this type of Return chart in 2011 to track and predict what would happen with Obama's Affordable Health Care act. The fall roll out of the computerized sign-up system was a mess. The Moon repdresented public opinion, Mercury represented the Public Interface, the volunteer programming help for Silicon Valley, the political statements, etc.
** t/Moon-to-n/Mars portrays how we project ourselves, express identity and confidence, push forward with creativity, use and manage anger, fight for survival or self-interests.
** t/Moon-to-n/Saturn is especially effective in portraying how people deal with arrests, constraints, depression, making plans and strategizing. I used both the Moon-Mars and the Moon-Saturn Returns in my blog side that covered the actions of the Scottish serial killer Brady on my blog site.
Any of these and other Moon-to-Planet Returns are highly useful. The cycles are short, one month long --- unless you choose to use a new and full moon half cycle. They portray emotions and changes and reactions (the t/Moon) relative to the expression of the targeted natal planet.
An interesting area I haven't yet explored is the t/Moon to its own N.Node (Draconic Aries point). Who knows. Dave