Hmm... My post doesn't actually state that the rune mage has the sword on his back, just mentions it as unreasonable, so I guess I'll just leave it as is and consider it a random thought. 

- As for most runeswords being too large to be kept anywhere else than on the back, then, well, I'd personally not attach those to people at all and just have wielders carry them around pretty much in hand if they have to walk somewhere with them. Just rest them on your shoulder when you are walking, and perhaps lean the flat tip to ground when standing still for a longer time. Sure, you have somewhat less use of one hand, but then again you can keep the unity-rune activated at all times if you wish, you do not have to release the thing from anywhere when you suddenly need to use it, and nothing would be hitting against your calves every time you as much as dare think of taking another step. ...The more I think of it, the more it starts to feel that keeping runeswords on one's back would be very obtrusive to simply walking indeed - not only is there something heavy, hard and somewhat sharp where your legs will be with every step (or the trailing leg will be with each step, anyway), but being essentially connected by single point effectively turns the runesword into quite hazardous pendulum even at less than running-speeds. 

Another slightly questionable thing would be the spikes on the hilt, which at least in some cases are pointed towards the holding hand? How is it ensured that those would not cut into the wielder's hand?

(I may have listened NG rant over these kinds of things one time too many ... although all people I know who actually practice sword-arts seem to do it. Hobby-induced peeves, I guess. I more relate to doing it with live-action stuff (the number of instanced where actors get severely injured by their own props is quite intimidating ... especially common seems to be for women to suffer from their own costumes trying to routinely murder them in all manners possible), the more flashier fantasy stuff generally not so much. I personally do not think I could make myself take Final Fantasy-style combat seriously enough to ever start criticizing it. Yeah, sure, it is utterly over the top ridiculous by all standards, but it's not like they're even trying to [i]pretend[/i] to have the slightest semblance to anything remotely realistic. [i][b]Soo[/b] much shiny...[/i]
 - Armor should preferably still look like armor, though, not something that is going to either fall off or stab the person in the breast as soon as they move.)