If by ‘explore’ you mean ‘visit’ then sure. Otherwise, we pretty much know what to expect - astronomy and astrophysics are no joke. On a human scale, visiting another galaxy means just seeing more of the same, so why even bother. Diversity of life forms? I think we have a better chance to invent and explore it in labs here on earth.
We are always expecting more of the same, until it isn't. We are constantly observing unexpected things. Both with regards to life (on Earth, obviously, since we didn't find life anywhere else) and with regards to celestial bodies and physics.
And this is to be expected. We are building models to match our observations. "More of the same" is the basic assumption, but it doesn't mean it is true. That's why we experiment: to verify our models and if found wrong, to update them.
The more things our model takes into account, the more we can expect it to explain everything, meaning the more we can expect to find "more of the same", but it is never a given.
I mean, we thought we had the universe almost completely figured out in the early 1900s, with just a few details remaining. The "details" turned out to be quantum physics and general relativity...
We haven't even finished discovering the diversity in life forms on this planet. I'm an astronomy nutter, with all of the possibilities it brings. However, I'm continually amazed when I remember that our little planet is covered 70% by water that we truly have not explored. We keep finding some new species when they do go looking. The diversity of life in water compared to on land is impressive.
There are many groups of insects that have a majority of species undescribed, chalcid wasps are all around you, everywhere outdoors, but so small they are never seen. Current efforts proposed to sequence the genome of every species are grand scope, and have good intention, but also, literally, impossible due to the vastness of biological diversity.
