I hardly see a Stylemaster. But I'm glad I did.
Actually, "V" engines are more inclined to create an imbalance (the energy and direction of travel of each piston, needs a piston going in an inverse direction to counterbalance it, and comes close, but doesn't), and a 8 cylinder engine only provides as much power as a straight 6 cylinder engine. The only reasons "V" engines are better, they are more fuel efficient, and more compact (length-wise).
When "V" engine tech came along, they had to design more aggressive engine dampeners, and improve suspension. Otherwise, people complained about feeling unsettling vibrations while driving. In-line or straight piston setups were naturally more balanced, and had better strength/torque. But, straight engines weren't as quick, were very long (main reason some cars had such loooong noses (which also made cars with longer wheel bases to have larger turning circles)), and I believe they also had a lower maximum RPM range.
In actuality, V8 engines were available back in this era (actually as far back as 1910's), but there were other issues which made using them problematic. Piston cooling, water-jacket design, fuel delivery, combined with an exhaust route all had to be designed to be more efficient. Because of those issues, V8 engines were more inclined to overheat, breakdown, or not have a very long engine life. Oddly enough, WWII allowed automotive companies, who provided engines for military aircraft, to fund research that made V8 engines much more viable.