I think that if you want to learn to use a sword you should try to find a modern style instead of something like Katori Shinto ryu.
So your argument is that if you really want to learn to use a sword, you shouldn't learn from a system that has been teaching and studying the use of the weapon for over 500 years, and which is reknowned for producing some of the greatest and most famous swordsmen Japan has ever known? Instead you should find a "modern" style of swordsmanship? The closest is Shinkendo, which is highly based on Toyama Ryu (a more modern system in itself), which is based on the swordsmanship of me such as Nakayama Hakudo, a swordsman of the Hasagawa Eishin Ryu, as well as Iaido, Jodo, Muso Shinden Ryu, and Shindo Munen Ryu.
If you study Japanese sword styles all you will learn is tradition. There is no practicallity to them.
There is no practical reason to learn sword arts. You do not carry a sword in the street, you will not be attacked by a rival swordsman, it is ludicrous to think otherwise. The reasons for studying swordsmanship are many and varied, but practical self defence just isn't on there.
For someone like me who is banned from owning firearms, swords are the only thing I can use to defend my home.
To begin with, I don't think they're the only thing you can use. There are plenty of other things around, without having the police ask afterwards "Why did you happen to have a sword handy?" forcing you to answer "Well, I'm not allowed a gun (which they will look into, and from the inference here I don't think will look particlarly favourably on you...), so bought it to defend myself!" You won't be looked on as being particularly, well, sane.
I need something more practical.
No you don't. See above.
I came up with my own style and it works and is acknowledged as practical for self defense.
Acknowledged by who? And if you are looking at sword for "realistic self defence" then I'm not acknowledging it as practical for anything, as there is a sense of reality that is desperately lacking.
There are styles like shinkendo that are much better for learning how to use a sword than styles that have a long history.
Shinkendo has it's good points, and has it's shortcomings. But of course you have trained extensively in the older systems to know what is best for learning to use a sword, haven't you?
As said above Shinkendo comes out of the older systems, so it has a real base. I have less confidence in your system, based on the way you are discussing it here.