@DolfLun - you have received great advise so far from many, and in particular
@CarolKing.
These are my thoughts:
If you want very small loads, the ability to take a hit and set it aside for later, and ease of use then this speaks to getting a convection vape. Conduction vapes tend to take a while to heat up (need to heat soak the oven) and will continue to cook your herb as they cool off if turned off after a single hit. Also, tends to take a few draws to get them going (which is not unusual with any vape, really).
This speaks directly (to me) to a log vape (Enano, Heat Island, Under Dog, Woodscents, etc). I understand you want "portability" but are no going out and about vaping. So, maybe transportable rather than full portable will do. I.e. log vapes will require plugging in but they can be left on all day, can have very small bowl sizes (.05 g or even less), and work perfectly when just taking a hit and setting the stem aside.
If you can't tolerate needing a plug, then something like the Solo II, which to me is a battery powered log vape, and I'm sure others may come up with more models, may be the trick.
Now as to butane powered vapes: Vapcap (VCs) - I own multiple OG VCs (the glass ones) and a Ti Woody. I have loved VCs and DynaVap since I first came across them a year ago. Personally, I favor my OGs over the Ti Woody but that's a long story and I'm apparently in the minority on this. It is mostly conduction IME but cools very quickly and certainly you can take a hit and set it aside for later without much negative consequence. But I also don't think that they are the universal nut that fits all bolts which is the impression you can get if you read any "what vape to get" threads. LOL The issue here is that I don't really see butane vapes as "easy to use" for a once a week occasional vaporist. You can inadvertently combust, you must be able to hear the click (not easy in the wind, with outdoor noises, or if you are at all hard of hearing), and its a bear to try to heat up one in the wind (I'm sure you can imagine that its even more difficult than lighting a pipe bowl in the wind as you have to keep the heat on longer). I love them, suggest you get one, but not your only vape. Nice cheap addition to something more sophisticated IMO. But, the VC is another around .05 G bowl size vape so there is that.
I have also used the Sticky Bricks OG and Jr. I preferred the Jr and like this vape a lot. But the same caveats apply as its a butane powered vape.
Milaana and MFLB, and other non-regulated vapes: I have no personally used any of these. But they are unregulated which means that your control temp by draw speed, power cycling, etc. These again don't seem to fit the "easy to use" for a once a week occasional vaporist criteria, IMO.
Grasshopper - I own one, I love mine, I have not had a single problem with it. However, even though it comes with a life time warranty, too many people are still having failures and need to RMA their device. If in the USA, not that big a deal, but reliability and robustness issues cause me to only recommend the GH to an experience vaporist who has other vapes in their stables.
SwiftPro/CFV - this might be an idea. Full convection portable. Yeah, the oven size is bigger than you would clear in a one or two draw mini-session, it is full convection, will cool down quickly to preserve your herbs (fairly well), heats up very fast (sub-30 seconds), is small, and takes no technique. Something to consider, perhaps.
On the subject of pre-filled carts, was just in WA state recently and got a chance to buy a cart for the first time. My criteria was all cannabis derived therefore no PG/VG/PEG to thin and all terps used to thin and re-terp needed to be cannabis derived also. I ended up with a Nectar cart which is steel, glass, and I believe a ceramic wick (NOT a fiber wick which was another criteria). I brought my own box mod (variable wattage battery pack) and found it to be excellent for very stealthy occasional draws as I traveled and stayed with family members. It was a bit expensive ($70 for a 1 gram cart) but worked exceedingly well for its intended purpose. The thing is, that although it worked and got me medicated, the effects were a bit flat (common for some concentrates) and all in all I do find flower to have a much more well rounded effect. I like concentrates (off my Liger for example) for power and a load of flower for well-roundness. But that would probably put you under the table. Do buy a cart when in a legal state and try it. My advise is to NOT go cheap....cheap carts have artificial thinners in the product, are made of plastic, and have lousy cotton wicks that taste burnt after a bit.
Best of luck. Hope my random thoughts were useful to you....but keep in mind, this is only one man's opinion and not worth more than that.