Best way for multiple users to edit same pics and catalog

Question

Dear All
Please can I pick your brains about how best to arrange things so that my wife and I can edit the same stock of photos (not necessarily simultaneously, which I take it could cause problems).
We will soon have bought (unless advised otherwise!) two Apple MBPs (since we tend after long days at work to edit on the sofa!).
I take the options are roughly:  external drives, sticks, cloud, network.  In detail …
A.  We keep the pics and catalog on an external hard drive which whoever’s editing plugs into their computer.  Downside: it’s a bit irritating when editing or showing pics to someone to have to keep an eye to ensure the USB cable doesn’t get knocked out; it’s somehow nicer to be self-contained.
B.  Same as A, but using a 512GB or 1TB memory stick instead.  Downside:  the sticks are still pretty big, so same downside as A, to an extent, and also (is this right?) I’ve been told that memory sticks are relatively unreliable.
C.  We keep the pics and catalog in the cloud and wirelessly edit them there. Downside:  perhaps impossible, or at any rate too slow?
D.  Same as C, but using some sort of on-site server or drive (I’m a bit out of my depth here), perhaps like Apple’s Time Capsule.  Downside:  perhaps impossible, or at any rate too slow?
Are there other options?  For example: is there an option where the pics reside on my MBP’s internal SSD but, in some very easy way I can get them onto an external drive if my wife wants to edit or take them somewhere?  (If there is, I should ensure I buy a MBP with a big enough SSD; otherwise, I needn’t worry about that so much.)
Perhaps there’s an option involving smart previews, which I am just beginning to get my mind around?
Any asdvice you have would be MOST welcome.
Thank you.
  David

Answer 1

2.  Keep the images (unlike the catalog) on a networked drive and edit either (a) them or (b) smart previews of them (stored, I guess, on the computer of whoever is editing them, either my wife's or mine).
Even though I have mentioned this a few times, you do NOT need smart previews if the images are available. It's an extra step, completely optional, done only for speed purposes, and to be honest, if your catalog is on a thumb drive, that may be the speed limitation, not the speed of loading photos. In addition, smart previews are stored with the catalog ... I do not think you can put them on a different drive.
3.  Keep the images (unlike the catalog) on my MBP's internal ssd, and network my computer to my wife's so she can access either (a) them there (when I am around) or (b) smart previews of them.
Using the SSD for images is not going to produce speed benefits, other than trivial benefits that you probably can't even notice.
a.  I take it 1 would deliver pretty good performance.  I sometimes worry that it might seem mad to get an MBP with a fast internal ssd if I then don't use that ssd for images!  But I guess the internal ssd will still deliver good speed simply in terms of housekeeping, I take it, even if the machine has to go to a stick for the images.  Right?
I remain skeptical that a catalog on a thumb drive would produce "pretty good performance", but I admit that I have not tried. I fail to see what benefit you think you are getting from the SSD, "good speed simply in terms of housekeeping" is a phrase that I am not understanding. Yes, there are benefits to putting operating system and software on an SSD, but that's not what you are talking about, is it?
b.  By contrast, I take it that 2 and 3 really would be quite sluggish on the original images option, i.e. if someone were editing original images located on a network drive (whether that's a third drive or my internal drive, with my wife editing them wirelessly).  Yes?
No. Here's a major misundertanding on your part. The speed of the drive where the images are stored has little effect on the performance speed of Lightroom. Ian Lyons did a study, read it for yourself. A network drive would not cause performance issues in Lightroom, unless the network was failing to perform. Wireless? Well that's a different story, who knows, you haven't specified what type of wireless or the speed of the wireless
c.  But would 2 and 3 work not only better, but pretty well, if the person editing were editing only smart previews?
Possibly, but I reject the premise that 2 and 3 are sluggish because of the location of the photos, it may be sluggish because your catalog is on a thumb drive.
d.  Even if so, IF I can get a thumb drive which is bigger for the images, there doesn't seem much point going for 2 or 3, and some point in not doing so, i.e. editing smart previews has its limitations, and on option 3 my wife wouldn't be able to edit when I was travelling (unless we'd taken steps in advance to make smart previews of all the relevant pics)?  Or perhaps this last point is wrong?  Does LR make smart previews, locally, of ALL pictures in the catalog?
Number 2 is a very reasonable solution, even without smart previews, it is fine if you are accessing photos on a network drive. The speed limitation is the speed of accessing the catalog on the thumb drive.
e.  What's the best way of backing up the images?  I currently back up the catalog BOTH to dropox and to (yet more) external drives that I then take off-site, to the latter of which I also backup the images.  I guess that's the best way?  Apple's Timecapsule sounds good but wouldn't get anything off-site.  And I take it uploading thousands of raw images to the cloud would be either impossible or costly in terms of time or money?
All backup strategies are best when they are automatic (i.e. don't rely on the human user to remember to do it) and backups must go on a different physical disk than the originals. Many people backup to the cloud, see for example, the commercial service called Carbonite. In your backup strategy for Lightroom, you need to make regular, automated bakcups of the images and also of the catalog file.