Each modified application has its benefits for different individuals. In your case, you already spent a ton of money on dana 30 junk and you don't want it to go to waste. Plus on 33s, you are probably right, dana 30 will suit you fine. This may be a mod worth while to you....nothing wrong with that
For me, I hate seeing people spend any money or time on non standard mods with minimal gain. This case is getting better brakes, and lock out hubs and spindles. I am a fan of all three....HUGE fan. (I despise unit bearings and ball joints for that matter).
The increase in brakes is nominal....I know cause I run the same stuff on my mj front axle. One is better off getting some black magic pads and turning their rotors than going this route.
The upgraded spindle is cool....big fan of being able to pack, rebuild, and maintain my set up there but dislike the way it is done here. On all the dana axles, unless there is a brake mount cast into the knuckle, the spindle goes first into the knuckle and the brake caliper bracket goes on top of that spindle and is held tight with studs....this case it is 3 bolts only holding the setup and the spindle is outside the caliper bracket. To me, this is a significant issue....not cool at all. For off road only and being trailered to the trails it may work....but on the road with other people and their families on the road it is not worth the risk. Going against a standard design will not get you any brownie points when defending it should the worst happen.
I do like the locking hubs....I run them on my MJ with the belief that they will break first and be the fuse of my set up.
If one has the skills to do mods like this, surely one has the ability to build a better axle all together where these features are done properly to a standard and the parts themselves all around are stronger. Building and narrowing junk yard axles is not tough and if one starts off with building their jeep this way it can be way cheaper in the long run if you didn't (waste) money on the dana 30 already. I guess everyone realizes this eventually but building an XJ the second time round most everyone would build their cars differently.....I have built a few so my perspective is from the 'other side'.