ok, snipped for brevity then...

The nodes in one are simply a subset of  two.

Right now there is no DNS seeding done by devcoin let alone DDNS seeding.

The real question to ask right now is if there a desire and will to create and maintain some DNS servers for this type of use.  If the answer is yes, then work on it can commence.  It really should not take too much if is it desired and committed to be maintained.

As for a review of where we are,  the dns seed code has not been used yet.   The first step would be to start to use it.  This may be done as simply as a few dedicated servers that do nothing more then serve a few known good peers.

As for 3, there would be no need to make this easier for the end user unless you simple mean, make this work automatically more reliably.

Tellings users to addnode is actually not making it easier for them.

As for your caution with DDNS,  the risk seems to be no more then the risk with IRC, and since these should be custom DNS servers, logic to reduce this risk can then be considered unlike the existing irc set up.