I like the overall build, but I fear you may have gimped yourself with too much defense. I would like to see a little DPS points in there. Also, you didnt put any points into Reverent Protection, which is a life saver at times. You can also buy a respec and place a point into shield of the chosen instead of Shield of the Hero.
I think you can take points out of Heartened Will, and place them into Small Arms Specialization. Take some from Unyielding Defense and place them into Martial Shield and Defender. If you dont like placing points into defender then that's cool too. I have a Paladin Riftblade setup, and I whip some PVE tail, and I can usuallly solo easy. I fear that tanking is only good in Dungeons and Solo Questing. Let me know what you think.
Little bit here, little bit there. Mostly into Paladin. I have no issues at all, in fact I can usually solo any rift including elites - invasion forces are a joke. I'm usually 100% by the end of it.
I understand what you mean about the damage increase, but holding agro doesn't necessarily equate to doing more damage. I take so little damage and I heal from Reaver stuff and Paladin blocking. I have around 40ish% block at all times. With the damage return from blocking and Reaver aoe, I never have issues with threat and I actually survive better with more mobs. I usually pull off of tanks higher level than I am when Rifting.
From my past experience of playing nothing but tanks and healers in almost every MMO I have played in the past 12 years, I have found that most Tanks bane are spells. Hence why I have put so much into spell damage reduction.
I thought about putting a point into Reverent Protection, but I can not figure out where to get the point from. With a 3 minute cooldown I find it hard to justify getting and even harder trying to find a point to pull away from another ability.
In conclusion, I do not really need to do more damage as I have yet to have any issues at all with threat. My goal was to be super efficient at tanking. Take as little damage as possible, healing the whole time, and holding agro. I thought about having two builds, one spell damage reduction oriented and one more melee damage oriented. The problem is most/all encounters have spell damage.