I would suggest they write the license so that Accessing the software over the network constitutes distributing the program and Invokes the requirement that access to the complete source is made available to every user who can access the services provided by the program over the network. And a Warranty guaranteeing that working access to complete source code is available must be included with the service offering, requests for source must be completed without fail within a specified time period, and with specified financial penalties to be paid to the user and to the authors for failing to provide the warranty or any breach of the warranty.
I mean, that's basically the Affero GPL, and IMO it's an absolutely toxic license.
I can't think of a single time when I've installed any major server-side web app without needing to make changes to it. About 95% of those changes involve things like tying in a custom, site-specific login system or other site-specific hooks.
I wouldn't feel comfortable making those sorts of changes available to the public, because doing so removes one entire layer of defense in depth from a security perspective. And even if that weren't the case, exactly none of those changes would ever be even slightly useful to anyone else, because they won't be running the software on my site, and won't have access to the user database or other infrastructure to make that code actually do something useful.
Because of that, I won't touch anything with an Affero license, even for personal projects. Almost no company, no matter how small, would touch anything under that license with a ten-meter pole. So the net effect is that Affero-licensed projects rarely get used by anyone other than die-hard GPL zealots, plus whatever company created them, where applicable.