Simple existence - Cosmological argument leading to God

[Jackalope]

The cosmological argument if sound [...]

Hold on.

Stop. Right. There.

First of all, you didn't state which cosmological argument you're referring to. There are several forms. For the sake of argument, I'm going to assume you're referring to the Craig's version of the Kalam cosmological argument (KCA), as it seems to be the version currently in vogue:

P1. Whatever begins to exist has a cause.
P2. The Universe began to exist.
C1. Therefore, the Universe had a cause.

Note that Craig formulated this version of the KCA in light of the evidence of inflationary cosmology.

The KCA is a valid argument - the conclusion (C1) logically follows from it's premises (P1, P2).

You've further asserted that if the argument is sound an additional conclusion can be deduced:

C2. The cause is both powerful and intelligent.

Here's a few problems with the KCA and your additional conclusion.

P1. This is an unsupported assertion. While it may seem intuitively obvious, there are observed phenomenon that appear to violate the assumed principle of causality. Two examples I can think of off the top of my head are virtual particles and beta decay.

P2. This is also an unsupported assertion. It is not known whether the universe began to exist. Using best explanation that we have (big bang theory), it is thought that prior to inflation, the universe existed as a singularity. The question posed by P2 is not properly related to what caused inflation, but rather to what caused the singularity - about which nothing is known. It has not been shown that it necessarily needs a cause.

Note that if you don't accept mainstream cosmology, then you're going to run into other problems with P2, particularly a lack of supporting evidence.

As P1 and P2 are (as of yet) unsupported, the argument is not sound, and the conclusion C1 does not have a known truth value.

Even if the original argument were sound, your added conclusion C2 is wholly unsupported as you haven't offered an argument as to why it must necessarily follow from the premises.