I'm sorry, Mike, but I can't help you on the DD-WRT front as I haven't used that firmware in a few years now. I'm running pfSense in a virtual machine with Ubiquiti & Cisco APs.
I wanted to get away from a platform-dependent setup with limited power and migrate into something that was easily upgradable and portable. A VM platform gives me that. One day I started to worry about my router failing and my lack of preparedness for when that happened -- considering how much was relying on my "non-standard" home network. Ironically... as I was making the transition it started to happen as the reboots and lockups were mounting. People balk at running a computer 24/7, but it basically runs my house and even with all the VMs I have running it uses less than 40w at idle -- it's an older i7 platform.
The benefits of using your own DNS servers really depend on your end goals. It could be because you want to get IPs from the root source, you want to protect your network from malware sites, you want to prevent users from accessing "bad stuff", or, as Pete pointed out, you want to get away from your ISP targeting you with ads.
That is easily done with pfSense. For DD-WRT you'd have to verify the hardware and firmware combo can do VLANs.
Personally, I use encrypted containers for all sensitive information. I also use a "banking only" virtual machine.
Not that it matters anymore considering how many times my information has been stolen from sites!!!
Another router OS you can utilize is OpenWRT in miniature these days. The little travel routers have two NIC ports which is all you need. Very low power devices these days.
This year started up with a small local bank thinking it would be better for us. Two months in to the new account the debit cards got comprised and it appeared to be happening from one of their clients which was a large fast food Francaise. 3 letters this year about comprised accounts and all included a statement regarding what I should do about securing my accounts. Really?
BOA here is closing all of its drive through stuff and only keeps one teller inside. Go inside and ask for help and the banker or customer service person will just call their CS number as they cannot get in to your account anymore. (wonder why?).
Thinking much this stuff is from within from unhappy campers.
@Mike ....You can secure your stuff at home but it really doesn't really matter these days as the many federal and many state tax databases have been comprised (probably too from within) due to willy nilly security and folks from within taking advantage of it.
Found a before Comcast cable bill from the 1980's. Saw a price increase there from $12.95 to 19.95 per month one year.
Here have been a Direct TV subscriber since the beginning (~1990 something) and first use was via a Sony receiver / dish at the time. I had a BUD in the back yard before that. Current ancillary sub has been the same for many years. There is no time contract on it. When AT&T took them over got a hard sell here to update my subs / equipment similar to what happened with Frontier taking over from Verizon FIOS. They wanted to renew my contract at a new rate for 3 years. I said no and that was that.