The overall capability of the Shahpar II is likely in-between the Predator and Reaper. I think our real shot at developing a Reaper-class UAV is furthering the PAC MALE UAV program. The current version of the latter is approximately in the range of the MQ-1C. However, if and when PAC gets a handle on that design, they can (like China and Turkey are doing) enlarge it into a 3-4-ton class drone analogous to the MQ-9.The American assessment of our UCAV is that Burraq is approximately the level of a Predator and Shahpar II is that of a Reaper.(Key word here approximate, before you start jumping on me).
(We seem to have gone for a short and fat UAV design).
The fact that the Shahpar II is significantly bigger in size, makes me think that it’s a Turboprop rather than a piston engine.
Looking at the NESCOM and PAC designs, it's starting to seem that the Shahpar-series -- if enlarged to an MQ-9-sized drone -- would go twin-engine, while the PAC drone would follow the Predator-to-Reaper development closely with a single-engine design.
The powerplant would probably be the main bottleneck as, at that point, the US will shutter any option using ITAR inputs (as it has sanctioned many of our major defence R&D organizations). Ukraine and Turkey would likely be our main potential engine suppliers at that point (I think China is unlikely as they wouldn't back a competing drone).
We could potentially get a 500 kW-ish turboprop from Ukraine, but ideally, we'd take in-house development a lot more seriously at that point. If we can't do 500 kW, we ought to at least get a start with a 100-150 kW design. In this case, we could have a dual-engine MQ-9-sized UAV as well as even upgrade our smaller designs and explore other projects, like a small twin-engine helicopter or a next-gen successor to the Mushshak-series. That said, the capacity building and expertise that leads a 100-150 kW design could lead to a 500 kW design and, 10-15 years from there, a 1,000-to-1,500 kW design.
Perseverance is key.