It ended up not being a problem last year, due to ease of getting a downtown room.  If I need to rely on the housing portal, is it possible to only accept a "suite" hotel?  Homewood type, etc?  I need separate rooms for my family and would love to stay downtown if possible, it was awesome last year.

What is available through the the portal is what hotels we have to offer. The hotel list will be coming out soon for you to look at.

Mike

So, can we pick the specific hotel when the portal opens?  For some reason I thought it was just first available, but I haven't used the portal yet.  Are we able to choose specific room types as well?

OP do what my group has done for the last 10+ years. Book it outside of the portal. 
Yes I know people are going to tell me you cant do that, that a hotel won't let you book a room during that time. They will. If you have the right level of loyalty points :)

The portal will allow you to choose from available hotels. So, if rooms at Embassy Suites or Staybridge Suites are available when you open the portal, they will be on offer, along with the respective available room choices. If all those blocks have been booked and the only thing left is a King bed single at the JW Marriot, that is all you will see.

Like Hahnarama, I always book outside the portal. However, this can be considerably more expensive if you do not have the buffs that come with loyalty programs, brand credit cards, etc. 

There is also a Homewood Suites downtown that has historically not participated in the housing block but has the kind of suite-style rooms you are looking for. Worth checking out.

I have to say, as someone who constantly yaps about booking outside the hotel block myself, it has definitely gotten more difficult in recent years.  Up until the few years the Moto GP overlapped with Gen-Con it was a breeze to get a cheap room outside of the block; the Moto GP years made it a little harder; then, for some reason, in 2019 Hilton started listing rooms at some hotels as being $999/night if you tried to book a year out.  When I checked in September for 2022, most hotels were showing they were sold out, and as a Diamond member I was allowed to reserve one room, but it was $500/night.  Big change from the days of plentiful $200/night rooms a year out, for sure.

(I will add that you really want to pounce if Gen-Con ever changes its dates again though; I got a downtown room for $89/night last year by getting a "long-term stay" discount before they noticed and disabled that feature during the convention)

There are separated-bedroom rooms still available at the Staybridge Suites downtown for $459/night. A spicy meatball to swallow, but if you really want a guaranteed room.

My point accrual is WAY DOWN

Yes and, not that it does any new members any good, Hilton has been pretty much letting everyone maintain their previous elite membership level status throughout the pandemic, which also makes getting rooms slightly easier if you were already up there with travel nights and points beforehand.