Is there a way I can see minion damage?

Just starting out again in SSF nee league after years of absence, and really find it hard to see what is benefiting my zombies and raging spirits much or little. There is no DPS indicator for lots of good reasons, and yet...

Am I correct in understanding that no modifiers from my own passives or gear (such as +spell damage, + damage, etc.) affects any of my minions at all?

If I get faster casting, I suppose I could get more Raging Spirits out, and that will help my damage incidentally?

Any other ways to compare how much my raging spirits are doing compared to, say, casting "spark" or another spell whose DPS is clearly listed?

On a side note: There are a number of support gems that suggest in the mouse-over that they support zombies or raging spirit, I just don't see how (e.g. bonuses to damage over time). Is that just marginally helping or should I just ignore it?

thank you in advance

PoB is the only real way to see minion DPS. And for passives and gear it must specifically state minions or it wont work for them.

For SRS though faster casting will allow you to get more out but it probably wont be more dps than another link that grants actual damage. Unleash support is what you want to use to get to max SRS count.

And yes generally speaking supports for DoT will not be that useful on minions unless you are specifically building for minion DoT (ex poison SRS).