Working indoors I have to use some R1, notably the points. With my latest plan I've tried to use R2, and even one R3, as transition curves and have only gone down to R1 where absolutely necessary. Having said that all my locomotives are 0-4-0s and I have shortened my US-style freight cars to around 22-25 scale feet in length (around 12 actual inches) with passenger vehicles only a fraction longer, so it all tends to look in proportion even when on the sharp curves.