By and large, titles are only barely meaningful. Every company has their own way of slinging the things around, and the ones that give out the fanciest titles often give them out in absurd numbers in lieu of pay. to the degree that they matter, what people think they mean is going to vary from person to person. Don't look at the name on the slot. Look at the job description. Figure out what skills and capabilities are necessary to be a "CTO", and what will help you learn those things.
Then take whatever you've concluded with a massive grain of salt, because CXO slots are hotly contested, which means that you basically have no chance to get one at a large company. If you did, you wouldn't be the sort of person who needed to ask for help on how to do it on a stack exchange site. Instead, you're targeting small startups, preferably real small. Getting that sweet, sweet "CTO" title as the second employee ever is a lot easier than grabbing it in a company of 100, which in turn is far more doable than in a company of 10,000. Small companies are invariably weird, with corporate culture shaped heavily by the founders. The trick to getting a top slot, then, is to find them when they're small, and be the thing they need at the time, and be willing to take a risk on them, and be good enough at spotting the good ones from the bad ones that the risk pays off. So good luck with that.
For your current company, the title matters even less, because they know that you got to pick it yourself. The problem with doing it at your current company is that they've probably already got a CTO, which means you'd have to displace them somehow or other. Still... figure out what it is that they do. Figure out what it is that the other higher-ups would like them to be able to do. Work on being better at doing those things. Try to set yourself up as the obvious successor to this person... while not making your interest too keen. I guarantee that having the current CTO see you as a threat will not do good things for your ability to become CTO.
So, having taken all of that into acount, if you really must have a suggestion for the name, I'd say that "Solutions Architect" sounds best. Like I said, though, that's going to vary from person to person.