Allthecool...
The question referred to whether or not you precede the taxi call or departure report to Centre with "BN/ML Centre, ABC, IFR Taxi/Departure" to give them notice of the impending report. The answer is NO.
As for broadcasting on ATS or a CTAF, both are required.
ENR 1.1 46
Summary of Reports - All IFR in Class G and
Summary of Broadcasts - All Aircraft at Non-Towered Aerodromes respectively.
Bloggs
Not trying to appear as a dickywhacker here, but I would probably tend to include IFR after the callsign on a CTAF call if only to make any traffic aware you may be emerging from cloud shortly. There is nothing in the rules either way here, but an "operating clear of cloud" call is required if that is the separation being maintained, so why not alert any VFR traffic that you are coming down and may not have the margin to see and avoid that 1000'/1500M provides? If anything, it may prompt a position call from the said VFR traffic? Obviously wouldn't need the IFR bit if it is SKC...