See tldr at the bottom.
At the moment Alora drops are 25% more common than 07 (I think) which is fine for most Alora content, but IMO it would be beneficial to make Nex (and maybe even Nightmare) drops slightly more common to make the content not dead. If we take a look at the individual drops of both the Nex and Nightmare;
Nex
Torva Set - Best strength armour in the game. However, there are not many players that are willing to spend over 1b per piece for slightly more strength bonus.
Ancient Godsword - Only viable in PvP situations (Pvp on Alora is pretty dead, making the godsword dead content considering there are 10 pkers on Alora).
Zaryte Crossbow - Good at "some" bosses such as Nex and it's good in specific situations such as speed running.
Zaryte Vambraces - Best in slot gloves for range, fair enough.
Nightmare
Inquisitor Set + Mace - Pretty useless set when you can buy a bandos set for 1/40th of the cost and it'll do nearly the same job for you. Sure, it has some niche uses such as the crush bonus for speccing.
Harmonised Staff - Pretty shit staff when the Sang offers better dps and healing, while costing 1/10th of the price.
Volatile Staff - Only viable in PvP situations (Pvp on Alora is pretty dead, making the staff dead content considering there are 10 pkers on Alora).
Eldritch Staff - Lol.
So as we can see from that list, Nightmare is pretty pointless to kill unless going for the collection log, while on the other hand sure, Nex has some good drops such as the torva set and zaryte vambs, but the issue with that is a 4 man Nex kill takes 5 minutes and if you're not in a clan then good luck finding 3 other people to kill Nex with you AND, from most people I've asked it takes a considerable amount of time to get a unique in your name at Nex anyway. My suggestion would be to make the uniques at both Nex and Nightmare slightly more common AND/OR buff inquisitor armour/weapon and buff the Harmonised Staff.
Tldr; Half the drops at Nex and Nightmare have niche uses or are dead content, make the uniques at Nightmare and Nex more common.