1) the names of God, are infinite -- in fact uncountably infinite. the simplest like "the king" etc, are meant to convey in LAYMEN'S vocabulary some attribute of God.
2) given an attribute like power, one is supposed to then take the limit of the attribute going to infinity. if you wish you can think of it like taking a calculus limit where the argument x --> infinity. clearly in taking this limit, such an attribute is "unlike any belonging to creation."
3) the other names of God are presumably more precise but difficult to describe using clumsy written words. they are probably described more aptly using mathematical terminology, however even that is hard.
4) your real issue is the following: is the designer of the universe, which is 15 billion light years across, a personal God? Does God have anything to do with insignificant clumps of stardust like us?
Most athiests believe in some sort of design in the universe (after all, remarkably, the universe is comprehensible). However they cannot make any connection between that agent of design (what we call God) and created beings like us. What should this agent of design have to do with us, they say?
The usual answer to that is formal religion: religious texts, and religious experiences. If religious texts make sense to you, and not seem like a sham, then you will be inclined to believe that the agent of design really really is the agent of good mentioned in whatever scriptural text you are reading. Also, people have personal experiences whereby they put their trust in their "personal" God and pray for help, assistance. Many people believe that their prayers are answered, at least in part, and that helps solidify their belief that the agent of design is a God which actually has something to with humans, etc....
5) About monotheism, well the universe seems to make sense and seems to be governed by a UNIFIED set of laws. The agent of design, assuming it exists, must also show manifest unity in itself. This means the agent is presumably one, or at least unified into one broad cause.
In fact nobody ever seriously believed in polytheism. Everybody really believed in in different attributes of the One taking special importance -- which eventually became known to people as various Gods and Goddesses, etc. Almost always, this warping of the God concept was financially motivated -- more Gods for people to serve = more money for priests and religious orders. Islam came to wipe out this kind of petty financial relgiousity, and so on...
So monotheism is the cleanest implementation of the God concept....polytheism seems to make the whole God idea a joke...