Some great suggestions, from my experience living in a Balinese village for years.
It depends greatly on your relationship with the people, and greatly depends on their income etc. 3 times in 5 years is not a close relationship (not with Balinese).
The first thing is as you are coming back to Bali, not a first time visitor, you bring an Oleh Oleh, which is never rice, it is a souvenir, my kids want Oleh Oleh even if I have gone to Kuta.
2nd, rice is given as a gift from family to family at weddings, ceremonies etc, so unless you are attending a ceremony it may seem a little strange (unless these people are extremely poor and you are sponsoring them etc). It is given in a silver dish. I think they may be offended to be given rice in a bag if you aren’t in Bali all the time.
3rd, will depend greatly on their income and their likes, for example:.
I have Balinese children and we have 4 different sets of grandparents.
one set asks me to buy them gold when I travel (not that I ever travel abroad) and they will give me the money in advance,
one set always want good quality towels.
one set want anything, even the clothes of my back, so they love me to bring clothes, shoes etc.
one Grandmother wants anything from India, she is obsessed with India, so incense from India etc.
I would never give any of them rice if I went away for a long time and came back, or seeds or anything as such and I am close to these people (I see them 3 times a week). Once I had a friend buy from Australia every set of grandparents good quality towels and all 4 loved them so was on a winner there (I bought myself some too so it was kina of expected to share).
I have had on a few occasions had a grandparent bring out a "gift" from Westerners, they've pulled it out of the back of a cupboard and shown to me to ask what is this, what do I do with this etc. Visitors who have brought them something that to them is of no use or interest to them. A coffee mug from India does come out proudly a lot with one though.
As a visitor and not immediate family that spends time with these people I suggest you stick with an Oleh Oleh, it would be expected. You could do a good quality silk scarf for Mama and a nice leather belt for Papa, wrap them up and give them to them and DO NOT expect them to open them in front of you.
Definitely also take cakes to have with coffee, they will supply the coffee, but it would be expected you bring the cakes, and lots for everyone to share/try. You can also bring some chocolate from US, and biscuits not available here if you like, to have with the coffee, for them to try but don’t wrap that up and give that as a present, no way, that is food for all to share to catch up with you over coffee.