Right by the LeMay is a place called Freighthouse Square, an old railroad terminal that has been restored. It has some shops, and a food court in it that has 8 or 10 food stands, with tables in the middle.
I know you're thinking, a food court? But this place is great.
I can't decide who's friendlier--the guy who runs Paya Thai Fish & Chips (bald headed--you can't miss him) or the two brothers who run Little India Express. I'm not the type to get buddy-buddy with people I randomly come across, but I actively enjoyed every encounter I had at either place. They really do treat you like an old friend even if they've never laid eyes on you. I'd sometimes get it to go, and I'd always get back to the RV saying, "I can't believe how nice those people are."
If you can get to Paya Thai on salmon day, you're in luck. A giant hunk of salmon, with vegetables and rice, for something like $13 or $15 (last year). I'd see lots of people getting fish and chips, but I was partial to a hipster-type place in Seattle.
Over at Little India Express, we'd always get the chicken coconut curry and royal biryani, and on our last day, got an extra order of both to put in the freezer (and the guy gave us an extra container of coconut curry sauce just for the hell of it). When we ate it a few months later, I almost wanted to cry because I knew it would be a long time before I could have it again.
Entrees come with a lettuce salad with great dressing. Seriously--I'm not the type to chat people up or to become "a regular," but one of the brothers came over to see how our meal was and I blurted out, "Man, that salad dressing is good." He said they make it in house. Drat. But I mention this because I never get into conversations like that, but somehow these guys, and the guy at Paya Thai, make you feel like you're their cousin or something.
BTW, the LeMay is close to downtown, where if you have time, you should at least walk across the Chihuly bridge--it's full of Dale Chihuly glassworks. (You can walk, or take the free trolley from Freighthouse to downtown.) The Museum of Glass was surprisingly interesting. You can try it risk free (i.e. free) on the third Thursday of each month, from 5:00 - 8:00 pm. Don't neglect the Hot Shop, where they do glassblowing.
I never would have gone to the Museum of Glass if it hadn't been free, but I'm really glad I got to see it.
Let's see...if it were me, I would go on the third Thursday. Spend the day at the LeMay, eat at Freighthouse in the afternoon (I think Thursdays and Fridays are salmon day?) and get extra Indian food to go, and go over to the Museum of Glass at 5:00 (the Tacoma Art Museum and the Washington History Museum are also free during those hours--they're all close to each other).
We stayed at an unofficial place in Tacoma, but the
fairgrounds in Puyallup has RV spaces. I drove by Majestic Mobile Manor in Puyallup a few times, and it's okay--looked like mostly permanent residents. Or if you just need to stop in Tacoma for the day and overnight and don't need hookups, there's a Camping World in Fife quite convenient to downtown Tacoma.
The nicest place to stay in the Seattle area is Lake Pleasant way up in Bothell, very inconvenient for the Museum of Flight and the LeMay. There are a couple of RV parks out toward Issaquah, which might not be too inconvenient for the Museum of Flight, but not great for Tacoma. I haven't stayed at Dash Point, but the location would be okay for both places. And if there are two of you, you can use the car pool lanes.
You didn't mention the Boeing tour--definitely worth doing. That's way up north of all of this, in Everett. There are a couple of RV parks near there that I wouldn't stay at, partially because they're small for my 40-foot motorhome, and partially because they seemed kind of skanky. We stayed for about five weeks in Bothell, instead, which isn't an unreasonable distance from Boeing. But you can boondock up at the casino in Marysville--they have spaces marked out for RVs; we did the Boeing tour from there.
Gah, now I'm thinking about that dang Indian food. What I wouldn't give...