Suggestions for sandbox mode

Sandbox mode is an awesome addition to the game, though as it has been stated it's still on a very early stage, personally I think the first flaw of the system is that it's built around summoner's rift.

You could argue that it's done that way so that you could practice flashing over walls or figuring out minion flow but then, how about the other maps? there are much MUCH harder walls to flash in both Twisted Treeline and the Crystal Scar, of course you don't practice those because they aren't THE competitive scenario I guess, even though there IS a ladder for twisted treeline.

There's also the issue that champion picks, masteries and runes are mostly set in stone once you enter a map, this has been clarified a long time ago though, the system that rules over the maps is somewhat archaic and reworking it is quite the undertake, not to mention that in the real competitive scene, it's a feature that works for nothing since players are required to set these things during champ select only.

So basically these two issues can be solved with a small idea, a TRUE sandbox mode that is also map agnostic.

imagine an environment very much like Tron 2010, without any intricate textures but beams of light going through polygons, in this map you could summon walls (again, with incredibly simple textures), bots, jungle monsters and even minion waves. The map would be completely round (as the current icon for the mode) and it wouldn't be particularly big (imagine summoner's rift bases size combined) but it would have space enough to summon everything anywhere, you could theoretically even create custom maps by summoning walls!

The thing is that this map wouldn't be coded the same way the other maps are, this map should be so simple that summoning assets should be done on the spot, this way you could change champion, runes and even masteries, of course it would have a small loading time everytime you changed something but nowhere as long as it currently is since you wouldn't need to summon the whole rift all over.

This is merely speculation though and whether the system works like that or not only riot know but I believe it's a good base idea to start working on an enhanced sandbox mode! plus, any work done on a NEW map wouldn't affect old maps at all, so you can tinker as much as you want with the assets but the maps would preserve their sanctity!