Some Embassy info based on the "usual" loadout. Different Embassies may vary:
CDA and ACDA: BGen/Col/LCol. BGen and LCol are normally at Embassies with multiple Defence Attaches, although it has happened where LCols go to a one CDA Embassy if a Col isn't available and the LCol is doing a cross-posting. The huge Embassies like Washington and London have a bigger staff but I've never been to either so can't comment on exact ranking there. Any MOS can fill the CDA and ACDA positions, I've been at missions with Cbt Arms, CSS, Navy, Air Force...
CDA AA: Sgt - huge missions have more than one, probably reflecting a normal OR setup
CDA Ops: Sgt - not all posts
MSG: Single man post - WO although Sgts may fill if WOs are not available. Multi-man posts - WO, MCpl OR WO, MCpl, Cpl(s). Kabul is a different beast than the rest
CE: Two positions I know of, 1 Sgt and 1 MWO
Tour Lengths: For CDA it appears 2 years with the possibility of 2 x 1 year extensions is the norm. For MSG, 2 + 1 + 1 is the norm unless you go to a high risk missions at which point it is 1 year, period.
Family: 99% of the Embassies you can take your family. This may or may not include same sex partners. Extended family who are dependent may also be eligible for diplomatic accreditation.
Spousal Employment: This is not guaranteed. Many posts have no jobs available to spouses due to language, local laws or non-portability of professional credentials. The Embassy is also unable to provide any real meaningful employment in most locations except for perhaps 1-2 positions. Most spousal positions available at Embassies are generally at the entry level (such as preparing Immigration files) or menial level (such as escorting local contractors).
Accommodation: If you go to the US you are responsible to secure your own accommodation. Anyplace else you live where the Housing Committee assigns you. As stated this can be a lone apartment in a building, a guarded compound (maybe located with the Embassy, maybe not) or a house. It is possible to go to an Embassy on IR. You pay Shelter Share and Utility Share.
Schooling: If the local public school system is similar to what your kids would get in Ottawa, you use the public system. If it is so dissimilar that your kids would be unable to integrate into it or would not be able to reintegrate into Canada, DND will pay to have your kids attend a school which will allow them to do this. If a suitable school isn't available at your post, you can send your kids to boarding school in Canada or a 3rd location.
Language Training: CDA staff get 8-10 months in Ottawa prior to posting if going to a non-English or French location. Spouses are eligible to attend a certain amount of that. MSG do not receive any language training prior to posting. Once on post, MSG language training is dependent upon the post funding it. Some posts do, some don't.
Car: You can apply for permission to send a vehicle but the Ambassador must sign off on it. Some countries do not allow you to bring a car as a matter of policy. You can also purchase a car tax exempt locally and there are normally a ton of "diplomatic sale only" used cars on the block. The problem with taking a North American car with you is availability of parts and qualified personnel to repair it. Adds a bit to the repair bill to have a quarter panel shipped around the world after an accident. You are also required to either take any car you have not paid duty and taxes on, sell it to another diplomat OR pay the duty and taxes prior to disposal before you depart the post. This may also apply to foreign brand vehicles which are assembled in Canada. The parts may or may not be the same even though you have the same model of vehicle.
Pets: Subject to local laws, you can bring pets and CFIRP will pay for that out of your custom portion.
Medical/Dental: If not to the Canadian standard (or too expensive) you will be Medevaced out for serious issues. Same goes for your family. You have to front the money for medical treatment you receive anyplace which is not a CF or Allied facility and seek reimbursement through DND or PSHCP. This can be VERY expensive (particularly if it is a MedEvac) and DND will give you an advance when possible.
Mail: All Embassies are eligible to have legal documents, bills etc to post via white bag. Some posts are eligible to receive mail via unclassified diplomatic shipments. For those posts with this privilege this includes a set weight for parcels and unlimited letters. They can also send letters, photographs and cards back postage free to anywhere in Canada. Unlike the CF postal system, you are unable to send parcels, CDs/DVDs back via white bag. Posts without "parcel privileges" must have personal mail sent via the International postal system. If you are lucky enough to be posted close to a Unit with a CFPO address, you can make use of that.
PT: As just announced via CANFORGEN, no longer exempt. If the Embassy has a fitness facility of ANY sort, that is what you use. If no facilities are present then you will be reimbursed the cost of a gym membership.
Taxes: You are not subject to local taxes such as VAT. In most cases you pay up front then submit a claim to the host government
AOR: Many posts are responsible for more than one country. In these instances you would be accredited in each of those countries and do TD there as required.
Promotion: If you get promoted on Post and it would result in an over-ranking, you are normally posted that APS, even if you are only completing your first year. There have been instances where appointments to MCpl have been deferred until Dec to allow the member to complete their 2nd year and members of the CDA staff MAY be allowed to stay over-ranked with the concurrence of their Career Manager.
PERs: If you have a CF supervisor, they write your PER. If you have a DFAIT supervisor, they write your PER which can be...interesting to say the least.
Chain of Command: The CDA is not within the MSGs chain of command. MSGs are seconded to DFAIT and report to the Head Of Mission via the Mission Security Officer. MSGU does have an HQ element located in DFAIT in Ottawa and MSGU now belongs to the CFMP Group.
Anything I missed you're interested in for use in 15 years time?