I think, the biggest improvement area for PAK pacers is new ball bowling. No matter what else you do, there is nothing more important than conventional skills for a cricketer in any skill. It's really frustrating to see young pacers with good potential doing funky things with their grip, seem position, run up .... eventually fading away in couple of years time. Faking age is indeed an issue, but that's not the case for Hasan Ali, and it won't be an issue for Naseem or Shaeen - even with buffer, their age is perfectly acceptable for a 10-12 years career at highest level.
I am not comparing and don't want to hurt anyone, but to be honest I was impressed with the technical skills of Ebdat & Rahi in recent IND tour - they had proper grip, wrist position, delivery stride and release - didn't over step even bowling at their peak speed, didn't land on danger area and released from quite close to sticks - these are fundamentals upon which you can build on. They might not develop much because of lack of mentoring and competitive edge at domestics, but Saifuddin improved remarkably under Ramanayeke.
30-35 years back India started to nurture fast blowers in similar line - building on fundamentals and they are cashing on that. TA Shekhar or Bharat Arun are not sparkling names like Lillee, but they have done miracles with Indian pacers and each of them are very good with their new ball skills, disciplines, direction, control, intelligence and stamina - average speed has increased remarkably. When Streak was our coach, I saw our pacers improving considerably on the basics, but overall quality wasn't there. And, now Ramayanake and the Aussie guy (forgot name), is trying with U19 kids and their fundamentals are actually better than the national pacers few years back - we may see couple of good prospects in upcoming U19 WC.
In that regard, I think I have to say - PAK needs foreign coaching resources for the fast bowlers as well - for National team and NCA; these Aaquibs, Waquars, Mo Akrams or Azhar Mahmoods are not contributing much in further development - PAK need to step ahead from old ball and speed gun.