W/L % shows it has not been successful unfortunatly, and in pro sports after 3 years that pretty much the most important thing you will be judged on, especially when you have had some very talented players come through your program, we were not void of talent and came last as a result.
Even if he is good at game prep, development, etc, the players love him and even if Dean and Daryl do rate him it would be a crazy business decision to not replace him.
If Marty were re-signed as head coach it could well kill the club as most fans would be very very annoyed, many may decide to boycott memberships, etc.
As an assistant to work with the players development, etc may be ok, but doubt that would happen at the 36ers, very few go from Head coach to assistant coach at the same club.
Marty should either try and get an assistant gig at a strong NBL club like Perth and then hope he gets another crack down the track, after he can make a few changes to his philosophy, head coach a SEABL team to some titles/very strong seasons or try and get back into a role where he can focus on developing talent like a AIS type gig which he came from and was very good at. To be honest wouldnt mind him being a 2nd or 3rd assistant at the boomers, can work with the guys many of whom he worked with at the AIS and seem to speak highly of him but have a very minor/if any role on game days.
At the end of the day its a case of Marty thank you for your efforts, unfortunatly it hasnt worked, so we have to make the change, we wish you all the best in your future career. I'd have this chat to him ASAP, before the end of the season so both sides can move on, no point pretending there is a chance of renewal when there isnt or atleast shouldnt be.
So please sixers make the change, be proactive, if you are not already starting working out guys who you would target for the role and start speaking informally to them/their agent to guage interest, there are many good candidates out there at the very least they should be having informal chats with Maher, Gleeson, Stacker and various other good candidates most listed by Boty in a blog a few weeks back.
Get the coach signed up ASAP, even conduct interviews over the next week or 2 as most of these guys are not currently NBL coaches, well before the free agent period starts so they can get straight on recruiting/retaining top free agents.