I much rather prefer he was dead.
There is a chance he could be freed just like that Mullah who ran the Red Mosque.
This is true, if put in regular court system he will be freed without by SC verdict on some technicality or "lack of evidence" (despite his statements to the media over the years) or enjoy VVIP jail cell at the least.
If kept in army/ISI safehouse, he may also be returned in exchange for some kidnapped soldiers.
Best would be Gitmo for him now. However, it is also good to see he could not become another "martyr".