'Let's get some perspective here' would mean looking at something in a different way (or different ways). Standing on top of a desk in your classroom for example, would give you a (literal) different perspective. Different people would have different perspectives, even if they're viewing a situation or item that is the same. Saying 'Let's get some perspective here' would mean to look at something differently or to consider another viewpoint. Both your examples of 'various ideas' and 'looking far ahead' can be correct.

I would understand "perspective" here to mean "context".

mutual understanding