I'll try answering your queries pero these are just my opinions ha
If you intend to apply using your husband's family name, I think it is better if your passport and medical information sheet will show your married name and status.
After getting married, you can change your signature or opt not to. I do not think how your signature looks like will affect your application. Just make sure that you use only one signature.
PSA copies of marriage certificates takes months to be released the first time but you can request for an advance copy. You can ask the registrar's office where you will be applying for marriage license about the procedure
I am not sure but I think once you finish requesting for an advance copy, your NSO copies can be released in 2-3 weeks time.
Pero right after marriage, makaka kuha agad kayo ng LCR copy ng MC ninyo. Hindi ko lang alam if pwede ito gamitin sa pag change status ng passport.
In case hindi tanggapin ang LCR copy ang advise ko, proceed with your application. Use your married name in your application forms. Submit your existing passport even if it bears your maiden name. AFter submitting all your application to Missassauga and while waiting for your SA, you can apply for a new passport with your married name and get an NBI clearance using your married name. That way, when your application is transferred to MVO, your new passport is already ready and you can immediately inform MVO of your new passport number and name. Also, you can readily provide them with an NBI clearance bearing your married name