Google's messaging app actually has a desktop browser based client that you can use to send messages from your computer. So that might actually be a good solution for you. I use it regularly and have no complaints about either the phone app or the web app.
The one bug that I've had for a long while now is the "auto resend as SMS" feature that's supposed to kick in if the RCS chat fails, takes forever to work. It's much faster to just manually hit the send as SMS option if there are issues going on.
It uses the Signal protocol for its encryption so they went with a well known and proven option, but metadata isn't encrypted like it is with the actual Signal app apparently so it's not quite as secure.
A good chunk of my family uses Android and all have RCS enabled so I get to use it a good amount and it's been pretty solid for me.
Edit: the desktop app is actually just a PWA website so that might be able to get around your work PC's restrictions on installing apps.
I moved to Google Messages when Signal dropped SMS support and it's been fine. Most people I know who aren't on Signal or WhatsApp are on iPhones, but there are a decent number who apparently have RCS so -- perversely -- Signal dropping SMS support had actually resulted in a net increase in my secure messaging.
That is why signal dropped support for it.theybssid it was to increase security because users could accidentally be using signal sending regular SMS. The way you got lore secure is not how they advertised the removal, but makes sense that happens in some cases. Same thing happened to me.
I used Pulse for so many years, but it's become a bloated husk of what it used to be. In terms of usability and features, I've found the Google Messages app to be a really nice improvement over it recently. Been using it for a few months now, and it's been much better for me. The RCS stuff is a nice feature that I really hope continues to find its way to other apps, cross-platform, etc.