Just got back from a great trip. We really enjoyed our stay there and will be going back. The DVC member benefits were there, just not very significant or visible. You did get a "fancy" pool band that sparkled and said "MEMBER" on it each day. Lots of people accumulate the bands over the various days they're there. We saw some people with bands halfway up to their elbow. We tried it, but honestly it's more hassle so next trip we'll just cut the old ones off each day. Also, our magicbands worked great for everything -- room charges, towel/band check-out, parking garage, room entry, etc. we don't even know where our room keys were as we never used them.
Your specific questions:
-- nature walk: we did not look into this one
-- free popcorn refills: Yes still there though we didn't partake
-- one free character picture: Yes, we got one from one of the CM's at the DVC model room. It's a "lithograph" of Aulani with a silhouette of Mickey with a surfboard in the foreground.
-- free gift at the luau?: Yes, this was a "Member celebration" pin. Acquired from the concierge by showing your Luau receipt.
You do get a few discounts here or there. I did get 10% at Rainbrow Reef (snorkeling), which I did twice. I tried snorkeling in the lagoon but couldn't see anything so went back to Rainbow Reef. FYI it's cold at first compared to the pools but you get used to it. No DVC discount for the pool bar/roaming waiters though. The fish feeding times filled up within minutes (you need to line up well before 8AM). We weren't interested, but if you are, be aware that they sell out quickly. Snorkeling was way better than the fish feeding tbh.
---Also what are some other things to do there?: There was also a member celebration on Monday morning at 8A on the Luau lawn. We originally signed up, but ended up not going as we were busy packing as that was our check-out day. We could see it from our balcony anyway. It was as described above, but I will add that there is no food (I asked and they said it used to be a breakfast but they got rid of it due to covid), and you have to bring towels or a blanket to sit on the ground for the duration. It's really more for the kids and I'd probably recommend it if you have kids aged 4-10 with you. We saw Stich, Chip 'n Dale, Donald and Daisy, and Moana.
-- Are they doing any welcome lei greeting?: We did not encounter any lei welcome greeting.
Other things that we did while there:
-- went on a late evening walk along the Ko Olina resort pathway. Such a pleasant temperature and evening. We meandered around and went through the Marriott Vacation Club which seemed like a nice facility, then walked back to Aulani on the sidewalk along Aliinui drive. That is a popular jogging path in the mornings.
-- Sat by the beach and read
-- Sat by the pools and read
-- Sat by the hot tubs and read
-- Swam in the lagoon, pools, and hot tubs
-- Went shopping (both on and offsite). BTW, avoid the
Walmart and area around it. Instead, go to the Target, which is closer anyway. There is a Costco there, too, if you're a member.
-- Went down the waterslides and floated the lazy river
-- Saw Disney's Luau, which was
excellent and really had a good time. Pay for the preferred seating. The Luau lawn is very
long so the seating in the back is quite a ways from the stage. The Luau food was meh. The drinks were also a little disappointing.
-- Had dinner at Makahiki, which was good, just a bit expensive with the Prix Fixe. I'll skip it next time.
-- Rented a convertible and drove around a lot, which was one of the best parts of our trip
-- Hiked Diamond Head
-- Went to Pearl Harbor
-- Took a sunset Catamaran Cruise
-- Went to a few local cafes/restaurants. Some some hits and some misses with the local cuisine.
We could tell there was a ton more we were missing and are already planning another, longer trip. Didn't see Polynesian cultural center, didn't see the sub museum at pearl harbor, didn't check out the USS Missouri, didn't go to the north shore, didn't see turtles or whales, didn't do ukulele lessons, didn't do paddle boarding, didn't do make your own ears, didn't do the ATV excursion, etc. etc. Lots of potential for a lot more to do, but we'll be back!