Based on what the other person has said, the speaker makes a proposal or gives his/her opinion or suggestion about what to do under those circumstances. Such patterns as ～ましょう(Let's ～), ～てください(Please ～), and ～がいいですよ(～would be good) often come at the end of the sentence. Vなら can be replaced by それなら.
V is either in the dictionary form or in the Vない form.
I would like to go to Hokkaido.
If you are going to Hokkaido, it is convenient to go by plane.
I don't plan on going back to my country during summer vacation.
If you are not going home, please come over to my house.
If that's the case, please come over to my house.