Re: I have a question about using sandbags as weights.
 

If it's strong enough to blow over the light stands, I'll bet the sound man is having a blast (pun intended).

Re: I have a question about using sandbags as weights.
 

I'm late to the party but this may be useful for future occasions:

I don't use sand bags at all. I have a number of Manfrotto L-Peso, 4.3kg Counterweights
https://www.manfrotto.com/uk-en/l-pe...terweight-023/
Three of these if necessary, one on each foot, should do the trick. C-stands may be better than standard light stands if the ground is uneven.

They are much more compact cleaner and easier to handle than sandbags - though problematic if you need to fly to a location obviously :- )

Occasionally I also use the weight discs off of barbells. I attach them by tying nylon cord through the weight to stands and tripods. These are also very easy to carry if you simply sling a loop of cord on your shoulder and have the weights hanging down. Many weights have plastic coatings so they are not as likely to damage anything thats fragile. Lots of pre-owned on Ebay I would guess.

If you are not pushed for time and are on soft ground you can improvise using some heavy duty long tent pegs and nylon cord

Re: I have a question about using sandbags as weights.
 

Have you considered canopy weights for use in pop-up gazebos? They are shaped like elongated tubes that are meant to be wrapped around the legs (vs. draped over them), and include a velcro strap that keep them securely in place.
A 40 lb. weight in the center of gravity should work with nearly any light you could put on those lighter-weight stands. Now, if you've got a large modifier attached, like a 4' softbox, then you'll want a c-stand, plus weights, and possibly even a guy line attached higher up so that the top of the stand doesn't wiggle around.
Always keep some paracord in your kit, tent stakes are super handy when setting up on grass (for guy lines), ratchet straps, zip ties, and gaff tape. With that kit, you're ready to tackle anything.