A128 Transducer Question

[scottor]

I am upgrading my vessels electronics by swapping out my C90W to an A128 (E70237LNC) w/ Chirp and need some help identifying the type of transducer I need. My vessel is a 2012, 250 EX admiral defiance fiberglass pilot house with a pair of outboards. My current equipment list is as follows before installing the new A128:
*Raymarine C90W (E62111-US)
*Raymarine DSM 300 (E63069G)
*Raymarine Digital dome (E922130 18” )
*Simrad AP-24 auto pilot
*Simrad AC 12 computer and a RC42 compass.
*Airmar 20 degree tilt transducer
*IC- M412 VHS radio w/ MMSI
The current Airmar transducer could be swapped out for a chirp version B175? Which is a low profile but I want to know if I would get better performance from a B265 - 1 KW? In the future I may swap out the original airmar 20-degree location low profile for a side vision transducer.
I assume in my studies for this swap that I do not need the DSM 300? If I do decide to add the side vision feature will I need some other type of sonar modular? CP-200?
Thank you in advance for your feedback.
Scott in Charleston, Oregon