Is there a way to increase the space for plotting when making a unbalanced grid of plots. See the below, where max area is unutilised.

```
library(gridExtra) 
p <- ggplot(data = mtcars)+geom_point(aes(x=mpg,y=mpg))
grid.arrange(p, arrangeGrob(p,p,
                       p,p, 
                       heights = c(1/1.5,1/1.5),nrow=2),
         nrow=3,heights=c(1,1.2,1.2))

```

[![enter image description here](https://i.stack.imgur.com/heRns.png)](https://i.stack.imgur.com/heRns.png)