Early socket 4 boards were pricey as hell and you either got EISA/ISA or PCI on later OEM models. I heard of socket 5 VLB mentioned but never seen one, would have been too expensive for home builders and PCI was a better match anyway.
PCI's claim to fame was a separate clock from the CPU and you could use more then 2-3 cards.
Believe it or not, there was a time when the Pentium was available when people were still highly skeptical of PCI. Most of the Pentiums available during this time were either MCA, EISA, VLB or even plain old ISA! ...
The problem with VLB was the speed of the BUS was tied to the FSB of the CPU (and writing to the cards meant you couldn't read from CPU cache at the same time as they shared the same bus). It was hard making cards work at greater then 40mhz speeds (people had problem with the 486DX50's) so once Pentiums came out at 60 and 66mhz and greater VLB was in trouble. PCI's claim to fame was a separate clock from the CPU and you could use more then 2-3 cards.
I don't think wasted PCB space was too much of an issue in the early days since most PCI cards (other then Ethernet which was rare in VLB and sound cards that were nonexistent in VLB) in the beginning were pretty large. VLB cards seemed shorter to make up for a longer length.
Are we now talking Pentium 1's in general or Socket 4 which was the original question? I have P1's in EISA and MCA.