Sample Data Provided! Ranking Content Performance in Email Sends

Hello! I have searched the forum, but my question is so specific and I know so little I cannot identify threads that would answer my question.

I'm attempting to create a weighted ranking of content served in emails. I have done
some work already, but I'm not sure how to proceed. Thank you in advance for you help!! :tup::)

I've anonymized the data here:

See the 'Stats' tab for what I've done already. All numbers and percentages are made up, but based on real data and a real sample size. Assume this is my data as I would apply the techniques that we would use here directly to my real data.

Rank content by 'performance'. Our measures of performance are open rate, click rate, and the negative indicator of unsubscribe. However, I just have a very elementary understanding of stats.

My goal is to take my entire sample size here, rank the measures of performance listed above in a way that does not factor in the size of the sends so as to not favor those with large send volumes.

I will then weight the ranks by importance of the measure - so we've decided to rank them with the following weight out of 100. Sorry if I'm not using the proper terminology here also, I'm way out of my element.

Open rate: 20
Click rate: 70
Unsubscribe: 10 (this will ultimate be a negative factor in the score, so we'll probably multiply by -1 while we're summing the scores)

So a 1.5% click rate is much stronger than a 1.5% open rate.

Once I have the ranking system implemented we'll only rank those content items that have only

What I've done:
This is me just struggling through and thinking of what might be helpful. By all means, this could all be useless, or maybe I've hit on what I need to do! I have no idea. That is why I'm posting.

So, what have I done. I've normalized the open rate and click rate. I've taken the average of those two numbers. I will then add the average of those two numbers with the unsubscribe number* to get the 'final score'.

What I still need to do:
1) most importantly - is that the right way to 'rank' this stuff?!
2) I need to weight the scores, which I am just a google search away from learning how and doing.
3) Be able to explain this in simple english to non-technology and statistician types.

*I don't have the unsubscribe rate numbers, but I assume I'll be able to find them, weight them, and apply the negative score in the end.
Nobody has any suggestions? Is it too easy? Did I not provide enough data? Help me help you! I am willing - I am pretty stumped here so any guidance would be appreciated. I don't want you to do it for me, just help me figure out what to do and give keywords so I can teach myself.