Triggering review with selected files

Hi,

We use collaborator and it could trigger a review with a commit to bitbucket. However here are my concerns:

I could have a few commits into my repository before I want to initiate a review but every git commit in bitbucket triggers a new review in collaborator. I could delete the commits that I didn't want reviewed. However, now I have a commit and I would like 2 things:

1)  Add what files I want to be reviewed and not just the files in the commit. It could be files from previous commits that have not changed. 

2) In the first review I do not want the tool to collapse lines that didn't change from the previous commit nor do I want it to show a side by side comparison to the previous commit because the previous commit was not relevant. 

How do I accomplish this?. 

Thanks