Why wasn't Kaliningrad made to be bigger?

by xqcTF

Throughout the Cold War, and in the Eastern Bloc, the Soviets had pretty much control over the entire east of Europe. What I'm wondering is why wasn't Kaliningrad made to be bigger so that the Soviet Union could practically cut off the Baltic states completely from Europe. The Soviets having given Poland the old land of the German Reich could've easily cut off the SSRs from the rest of Europe, considering the fact that Lithuania has obviously always been against Soviet rule.

xqcTF

I'm talking about if Belarus and Russia extended their borders like this to separate the Batlic states from the rest of Europe