maybe putting this on a 3/1 for may be more appealing.

Vigilance + Regeneration = Nonbo

I find myself rarely considering activating the off-color abilities, except for Malmetal Construct. Maybe a rootwalla ability will be more appealing.

Otherwise I suggest to replace regeneration /w indestructible UEOT.

Though I agree generally with your observations, I do feel the need to point out your misuse of the term nonbo. They don't cancel each other out and actually work well together as your opponent has to choose if they want to lose a creature to get it takes down that turn or let it through and have to deal with it on the block.

Many people don't know regenerating taps the creature, since that rarely matters. It seems like a bad idea to combine it with vigilance for that reason alone.

Changed to pump plus indestructibility to give it effect on attack and block.

This version I find interesting.

...I really don't think repeatable indestructability is something that is a common effect. I think the rootwalla effect alone is a good effect on a vigilance creature.

I'd make it a 2/2 first though.

I, on the other hand, think activated indestructibility is a very suitable thing for common. It's much more suited than regeneration which has multiple fiddly bits. I think the game would be better if most cards with activated regeneration were replaced with activated indestructibility (probably upping the cost by in most cases).

On the other hand, I don't think a common should be able to block and kill a 5/5 every turn. +2/+2 and indestructible is too much (though I think it'd be okay if it could only be activated when attacking).

2/1 with +1/+1? Like a Thraben Valiant with a bonus.