INS Arighaat Sized "Baby Boomers" for Australia?

So INS Arighaat/Arighat [1] commissioned on August 29, 2024, is India’s second Arihant-class [2] small SSBN - known in the trade as a “Baby Boomer”.

The US’s first SSBNs were also Baby Boomers, called the George Washington-class [3]. They carried 9.86m tall Polaris SLBMs with a range of 4,600 km. Modernised Polaris sized missiles could (with lighter booster and warhead casings, smaller hypersonic warheads and more powerful propellants) have an extended range of 6 to 7,000 km.

The estimated 6,000 tonne displacement 1st and 2nd Arihants and even the estimated 7,000 tonne displacement 3rd and 4th [4] Arihants will likely be smaller and cheaper than Australia’s Virginia SSNs and SSN-AUKUSs.

Alternatively Australia could buy 4 x Virginia Block Vs [5] that are to have a much larger VLS missile compartment than Virginia Blocks I to IV. Buying full size UK Dreadnought-class or US Columbia-class SSBNs might one day be other options.

In a modified AUKUS Pillar 1 - if Australia can organise 6 SSNs by the 2040s we would would do well to complete our nuclear submarine fleet with 4 nuclear armed Baby Boomers as the best deterrents against China. 

The hypersonic nuclear warheads on Submarine Launched Hypersonic Missiles (SLHMs) could be nuclear shared [6] by the US. The legal and procedural precedent of US-UK pooled Trident II missiles might also be relevant [7]. This would of course involve removing the no nuclear "explosives" portions of the AUKUS agreement [8].  

The SLHM boosters might be an Australian invention or a US-Australian invention tested at Woomera weapons test range [9] in outback Australia. 

[1]  https://en.wikipedia.org/wiki/INS_Arighaat

[2]  https://en.wikipedia.org/wiki/Arihant-class_submarine

[3]  https://en.wikipedia.org/wiki/George_Washington-class_submarine

[4]  https://en.wikipedia.org/wiki/Arihant-class_submarine#Ships_in_class

[5]  https://en.wikipedia.org/wiki/Virginia-class_submarine#Block_V

[6]  https://gentleseas.blogspot.com/2023/01/us-nuclear-weapon-sharing-under-aukus.html

[7]  https://en.wikipedia.org/wiki/Trident_(UK_nuclear_programme)#Negotiations

[8]  https://gentleseas.blogspot.com/2024/08/a1-trillion-aukus-ssns-no-nuclear.html

[9]  https://gentleseas.blogspot.com/2024/09/independent-reviewwoomera-likely-for.html