The question seems to keep coming back to "will I be safer on...." etc.
You will be safer on ANY bike that you can control easily / properly AND don't try to do anything you're not comfortable doing.
Motorcycles by definition are an inherantly unstable machine.
That is, if you do nothing at all, the bike will fall over. You have to be pro-active in keeping the bike upright.
(for comparison, a car won't fall over if you're just sitting in it, this is an inherantly stable machine)
How safe it is, is entirely up to you, the rider.
Some bikes are easier to manage than others, so the question really ought to be, "which bike will I find easier to manage with limited experience"
If you're a complete beginner, never ridden a motorized cycle of any sort, then perhaps, visiting a few bike shops and having a sit on a few different makes / models to try them out for fit might be worth your while.
Physical fit is probably more important for a complete novice.
A bike you can comfortably put both feet flat on the floor, and rock gently side to side without feeling too much weight is likely to instill a greater "sense" of control in the first place.
A proper test ride would then help confirm suitability.
Me, I learned basic balance, clutch / throttle control on a cheap dirt bike, then once I had the "basics" working in a kind of automatic way, (do you usually think about every muscle you move while changing gears etc? , a learner does) I moved up to the bigger road bikes. Small capacity dirt bikes tend to be a bit tall in the saddle, but are generaly a lot easier to learn the very basics on because they usually lighter, but I'm six foot so "tall" bikes are not really an issue for me. If you're shorter in the legs, then go with a small capacity bike you CAN get yer feet down on first.
Like I said, just my 2c . Get on a bike, any bike, take professional lessons, learn to control it properly and safety will be in your own hands.