I'm not generally involved in alarms.
I think a system that can dial out to alert keyholders is essential.
Mine was recently modernised from Galaxy to Texecom and they used the existing cables. I did not want internet access or App control.
My cables are generally concealed under the floor, behind built-in furniture, in the loft, behind the bath, in plumbing ducts etc.
If you have recently decorated, I suppose you could conceal the wiring, and put it under the floorboards next time you take the carpets up. Laminate flooring is the enemy of electricians and plumbers.
I have a secondary keypad outside the bedroom door to save going downstairs in the night. It also bleeps if somebody opens an external door, even when the alarm is not set.
Each user has their own PIN and/or keyfob. Users can have a defined subset of powers (for example, guests or neighbours can't add or change other users, or disable zones); and perhaps you could permit cat-feeders to the downstairs room only.
It all works even if I am out of touch and the internet is down.
I have installed a couple of DIY wireless systems for aged and infirm relatives, they cost less than I pay for a year's maintenance, but always have an autodialler to call nearby trusted keyholders. IMO this is enough for the average Joe, and can be set to call if a panic button is pressed or if (for example) nobody has gone to the kitchen or bathroom in 24 hours.