To have a platform big enough to carry many tomahawk. similar amount does a destroyer carry today.
Quite.
When they were brought back into service, the Iowas mounted 16 Tomahawks. The ABLed Spruances and Virginas mounted just 8 each. It was this larger battery, combined with superior seakeeping (remember, launching from the Barents Sea was expected) is the main reason they were returned to service. They had a leg up on the proposal to reactivate Des Moines and Salem because there were four Iowas, and they had much larger fuel bunkers that could support smaller escorting ships when deployed. With the proliferation of the VLS refit Spruances, VLS Ticos, and Burke class destroyers the need for the Tomahawk deployment capabilities was reduced, and combined with the high manning requirements, the ships were pushed back into reserve and eventual decommissioning.
In my opinion, if there were a quartet [you need this many to make any sustained deployments of strategic Tomahawks work] of Alaskas that had survived (with the associated logistical train) in the reserve fleet into the early 1980s, they would have been a close competitor to the Iowas for reactivation. The power plant that the Alaskas used was still in USN service aboard CVT-16, and there were 4 other complete sets aboard Oriskany, Shangri La, Bon Homme Richard, & Bennington. They might have lost the aft turret for additional power generation and deck space, but it's a hypothetical that has fascinated me for some time.