Hey. I think I agree with you. There are limits on Gods power imposed from without (ie the laws of logic and mathematics) and from within (that he has promised to not lie etc). One could see them as limits... But the notion of limitless power is contradictory (and hence cannot be the case). The same issue arises in the problem of evil. I'll note that I'm including the problem of evil so as to better contemplate God's nature and NOT to prove that God doesn't exist. It seems that we might be forced into some conceptual revisions as to his nature, however. The problem of evil is as follows (and I'm sure it is an issue that every believer and non-believer has grappled with on some level)

P1) God is all knowing (follows from conception of God in Judaism, Christianity, and Islam)
P2) God is all powerful (follows from conception of God in Judaism, Christianity, and Islam)
P3) God is all good / kind / loving (follows from conception of God in Judaism, Christianity, and Islam)
P4) Evil exists (follows from Judaism, Christianity, and Islam). I'll also provide a couple examples to support this premise. Evil can be split into two different kinds:
NATURAL EVIL: Hurricanes, volcanoes, natural disaster etc that lead to suffering / loss of life.
MORAL EVIL: Rape, torture, genocide etc.

Now...

Either God CHOOSES not to prevent evil (in which case he is not all loving)

Or God CANNOT prevent evil (in which case he is not all powerful)

Or God DOESN'T KNOW about the evil (in which case he is not all knowing)

So... Something has to give...

This has been debated by theologians for centuries in order to... Come to a clearer conception of God's nature...

Theologians who attempt to hold onto the first three premises in the face of the problem of evil offer what is known as THEODICIES. (There is such a tradition of this that the defences have come to be known as theodicies).

I think it is fair to say that the most common line of defence is to say that God's power isn't limitless after all... And to offer a defence along the lines of:

This world is the greatest of all the possible worlds (with the good to evil ratio). Hence... God could not prevent the evils of this world without a reduction in overall goods.

This is really controversial, however. You just need one instance of an evil that does not seem to offer any good and the problem re-emerges...

There are lots of other theodicies that have been offered...

> have you actually considered what God says about himself rather than just considering what "mankind" supposes him to be?

I don't know what 'God says about himself'. I suppose one might find it in the Christian bible or the Mormon bible or the Catholic bible or in the buddist texts or the hindu texts or the old testament or the new testament or through prayer etc... How do we decide what 'God says about himself' compared to what people have said about God????

I have no idea...