In my own opinion based off my own experiences using Dolphin sites for probably around 12 years before moving over to UNA here is what I found:

Having "too much" can be the very reason you site doesn't succeed. I did the same exact thing as you mentioned above. Spending $1,000's in modules and custom modules to make a site where you could "Do it all". EVERY one of those sites failed. What I mean by fail is, sure you may get a bunch of members to join, for them to say it's a cool website, but....logging in less and less until they do not return. You will even have those who join and never sign back in again. When I asked some of the users what they thought about my Mega-Site that I was so proud of, they responded with "There is just so much stuff" and "It's too difficult and hard to navigate".

So I had to tell myself the actual reality.. I would NEVER be able to build a "replacement" site for those Giant, very well established, millions of active users, and very well funded social networks. So the conclusion, don't try to be like them. Be different. 

Today, people want to be able to go to a site/app and do what they want and do it fast! For example:

Twitter - People login to a page where the can read/post/comment/like/retweet from a single page. BAM Done. Facebook - Most people do the same thing there as well and from a single page. The difference with Facebook is that you do have activity in Groups and Pages.
Instagram - Same thing.Read/post/like/comment.. .BAM Done.. 

So when you overload your site with so many features, when someone joins for the first time, they are going to see all this stuff and be like.. waoh.. where am I suppose to start?? 

So lets talk about your list of apps/modules that you have listed. Several of those were build off the "Groups" module and customized with some additional features. But does UNA have what you need? Let's see:

Timeline - Check
Privacy Settings - Check
Email - Check - Called "Conversations" here at UNA
Messenger - Check - can be used for PMs or group chats. I believe Alexey is working on additional chat features like Live Streaming.
Privacy Settings - Check
Blogs - Check - That is known as the "Posts" app here at UNA
Forums - Check - Called "Discussions" here at UNA
Mobile Apps - Check
Ads - Check
Social Media Logins - Check
Polls - Check
Points System - Check (this is a 3rd party app and purchasable)
Media Albums - Check
Profile Tags - Here are UNA I believe "@mentions" may be more feasible like James Zandreiatti
For all of you "Specific" pages - You can use "Spaces" app to create what is better known as "Pages". You can have "Parent" pages with sub-pages under that. For example, you have Schools and Bands mentioned above, You can create these 2 Spaces and if you want, create additional Spaces under those. 
What I am getting at is that you can do most all of that with UNA. And now, I save the very best for last...

You can convert your pro Dolphin licenses to a UNA Pro plan at no charge by emailing support@una.io with your UNA Username, Bonnex Username, and the license you want to convert. This will give you UNA platform, SysAps, Core Apps, and Pro Apps. You can see them here: https://una.io/page/features

So if you already have hosting and a Dolphin license, you are not spending anything more than what you already are... for hosting.
I would like to offer some friendly advise though. Make your site different, unique. This will help target audiences (new members) and keep interest in your site for people to continue returning.