I agree on physical workout. I went to work with my bike most of the year (about 45 mins single trip) and stopped for about 1.5 months now (weather getting bad).
Because driving my car is more stressful I feel I take my job home sometimes, this does not happen when I go by bike.
Workout really helps.

Next: Why are you so important for your company?
If stuff breaks, does this really mean the company goes down the drain?
And you are the only one who can fix this?
Time to ask for a huge raise!

Get rid of this feeling.
When you cannot do your job tomorrow for whatever reason and IT fails the company will not go bust.
You have a job, do it well. When you close the door when leaving for home, work is gone.
When people call you in the middle of the night, work starts the moment you log into the system.
Between this it's your time, your life. Do something usefull with it instead of living in fear.

The problem isn't GUI vs CLI.
The main problem is automation.

If you need to do something once a day a GUI will do just fine.
Do the same thing 100 times a day and you scream for an automated process.
CLI often has more possibilities for automation.

Having said this, the solution is not providing a CLI for those tasks but a way to interact with the system that requires the least human interaction as possible.
This can be CLI, but also some kind of listening process that picks up a file or data in a message queue.

Too bad they don't give Darwin Awards to people who live to tell their stupidity...

What exactly did you ask those banks?

If you ask: "hey, can I get online access to BIA or SWIFT messages" they will come with very expensive solutions.

However, do you really need that? My company works in financial business and most of our SWIFT messages are send out a couple of times a day.

And bank statements (MT940) is retrieved once a day.

The moment you start asking things that have never been asked before banks will have some problem delivering.

I can give some horror stories from corporate experience about interfacing with some of the big names in the financial world....

But maybe you can explain the exact situation to them, why you need specific data.

And they might well have a better solution that would fit your needs at a reasonable price.

Or see a business opportunity.

I've worked for a large govt organisation with 6000+ users, which had 4 field engineers for remote locations (about 2000 users) and 15 sneakers for the other 4000 at their main location. Add about 10 helpdesk employees and 20+ network/server admins and you get an idea. However, this staff was needed because the huge amount of different applications run there.

Another site I worked at had 4 people at HD, 2 server admins, 1 network admin and 2 or 3 sneakers on each of two locations. Roughly 600 users

I'd say it's all about the number of service requests you get and the complexity of the IT environment and not absolute numbers.

Add SLA's and what users/management expect to determine if you are understaffed or not.