Here's a view from my Catholic background.
Is Suicide Immoral?
Some actions truly are neutral. How I like my steak done is not something likely to be weighed upon in the courts of Judgement (though the way some people talk, you'd be forgiven for thinking well-done was worthy of perdition).
If suicide is a morally neutral action, then it does not merit entry into Heaven; so what does?
If suicide is a morally positive action with your given motives, then can it merit entry into Heaven alone for the reasons you have described? That is, the desire to be with the creator?
A few different cults spring to mind when I consider this notion. Heaven's Gate seems to be the most obvious one; the desire to shed this world to be with the Higher.
One thing strikes me as the most obvious problem with this view; if it's true, it creates a death cult immediately, and the only rational action for anyone in a state of grace is to immediately commit suicide. Beyond the argument that this is patently absurd, it also doesn't mesh well with orthodox theology regarding God as a being of Life and Goodness.
The State of Grace
Perhaps more importantly, your proposition also requires that the soul be in a state of grace. That is, your soul has to be in a state where, if you were to die, you would indeed be admitted entry into Heaven.
However, orthodoxy teaches that nobody is within this state of grace by nature. It requires the repentance of sin and the acceptance of Christ's saving grace, through his crucifixion.
In your alternative universe where suicide is not immoral, one could, in theory, be baptised then immediately commit suicide in order to gain entry into Heaven. Indeed, in early Christendom, it wasn't uncommon for Christians to delay baptism until the deathbed, possibly with the view that one could thus sin freely and be cleansed "at the last moment".
But, this presents a new problem; how do you spread a faith where every adherent immediately kills themselves?
Beyond Heaven and Hell
My understanding, though this may be foggy, is that there have indeed been certain heretical cults who've taken a death-immediately view. Notably, the Circumcellion cult was known to attack Romans in the street, in order to provoke retaliation and "martyrdom". Little more than suicide-by-cop.
More pertinent to your question and its framing though; what if there's no Heaven and Hell? After all, you didn't ask about salvation. You just want to not fall into vice.
In this situation, I'd argue that suicide isn't immoral, because there's no morality to violate. From that though, it's likely that suicide is somewhat foolish if opportunities for personal pleasure or happiness arise.
There's no cut and dry answer to a theoretical question like this, but I would say that at the very minimum, weighing up the different views, suicide is a foolish action.
Whether it has virtue depends on whether you believe in a notion of virtue at all.
Disclaimer: Of course, the Catholic orthodox position, and the one I personally hold and believe to be true is that suicide is a grave sin. As a general aside to anyone reading this; please don't kill yourself. Been in that place before and it isn't worth it. Love y'all.