Sony Rx100II, what gear to get for beginner?

I own a Sony RX100II with a Meikon UW case (www.amazon.com/gp/product/B00TJSVSVE/ref=ox_sc_act_title_4?ie=UTF8&psc=1&smid=A12LB5MEUIY3R7)

Keep in mind that I am totally a new beginner in UW photography.

Gear I am thinking of buying at first:

Strobe:

Sea&Sea YS-03 (www.amazon.com/gp/product/B00PL58M0E/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=A1FQLMYBVOU9LM)

Arm:

Meikon 8"/22cm Aluminum 1"Ball and YS Head Adapter (www.amazon.com/gp/product/B00PC74L1A/ref=ox_sc_act_title_2?ie=UTF8&psc=1&smid=AQ8OKFKGYBQUR)

Clamp:

1" Ball Clamp (www.amazon.com/gp/product/B00OB2H78G/ref=ox_sc_act_title_3?ie=UTF8&psc=1&smid=A12LB5MEUIY3R7)

Lenses:

Any idea on macro and wide lenses that fit the 67mm thread of the MEIKON case

Gear for further on:

Aluminum Tray/Grip (www.amazon.com/gp/product/B00PGQSO6K/ref=ox_sc_sfl_title_1?ie=UTF8&psc=1&smid=A12LB5MEUIY3R7)

Another Strobe, Arm and Clamp as listed earlier.

Anyone have tips on what gear to buy first, not to buy?

Please let me know, it will be much appreciated.

 

Lenses:

Any idea on macro and wide lenses that fit the 67mm thread of the MEIKON case

 

Let me suggest a bit of caution here. I had a Meikon case for a Canon G15 and it had a 67mm thread, however it was not done quite right and allowed cross threading and was difficult to get a lens threaded onto it. I dropped two lenses this way having them fall off in surf or while swimming. One I recovered, one I did not. So make sure it's secure.

That said, any of the lenses discussed for the RX100 should be good choices, which housing you have does not matter. (I'm not a RX100 owner, so I can't give you specific advice, but you might check out the backscatter.com article on the RX100 series.)