Hey! I'm going to do my best to answer what I can about pre-Islamic Arabian polytheism, although lack of information around this topic, like around many from 1600+ years ago, makes giving a definitive answer difficult.

When referring to Mecca itself, where Islam eventually emerged, Allah was one of numerous deities - around 360 in total - housed within the Kaʿba, a large, square, stone block that housed portrayals of the gods and goddesses and acted as a sight of pilgrimage. However, Allah himself was not particularly important in his own right. Some scholars argue that Allah is related to the Semitic god El and was seen as a creator god (similar to as you mentioned) that gradually took the backseat to more local and immediate deities.

What is more known is that Allah was seen as the father figure to 3 of the more important female goddesses in the ancient Near East - Manat, Allat, and ʿUzzah. These three goddesses were given special place among both the Quraysh themselves (the tribe from which Muhammad hailed and who controlled the Kaʿba) but also further abroad. For example, ʿUzzah was, alongside a god called Dushara, one of the two principle deities of the Nabatean kingdom that famously built and controlled Petra.

These goddesses were not linked to Abrahamic religions (although we do find mention of various gods the the Arabians may have known in the Hebrew scriptures) but they did have some analogies among Hellenic gods. For example, Allat was depicted in the same vein as Athena. Likewise, ʿUzzah (and occasionally Allat) is compared to Aphrodite.

One thing that is important to note about pre-Islamic polytheism (which I wrote more about in an answer here) is that there were gods and goddesses for every area. Although there were gods known throughout much of the Near East (ʿAthtar, Allah, etc), they would often be less important than the local deities of a particular town or oasis. This is summed up pretty well in the old Arabian proverb, "When you enter a village, swear by its gods". It was seen as much more important to have a god or goddess of immediate help than to cater the favor of a far-off deity (there is evidence though that local gods could "intercede" with a greater god such as ʿAthtar though, similar to modern Catholic beliefs about the intercession of Saints to God). We are therefor much more likely to find the inscriptions of a singular, local deity, such as Dhu Ghaba for the oasis of Dedan, than we are to find any sort of agreed upon belief about a more 'over-arching' god such as Allah.

I hope this helps! If you have any questions, I'll try to get back when I can. I'd also point you towards the other answer I linked, where I talk a bit more in-depth about both pre-Islamic polytheism and pre-Islamic monotheism.

Sources

Arabia and the Arabs: From the Bronze Age to the Coming of Islam by Robert G. Hoyland (which I highly recommend)

The Formation of Islam: Religion and Society in the Near East, 600 - 1800 by Jonathan Berkey

Edit: I don't proofread well.