It's going to be sourced from the years 2007-2009 on metacritic's best-of-all-time list. Here are my picks from page 1 of the list; the very toppy top critical darlings - with some notes. 

Super Mario Galaxy - I have a Wii copy, however, I recently learned about it being on the collection, Super Mario 3D All-Stars with SM64 and SM Sunshine for Switch. I'm going to hunt down that copy so I can use my Switch instead. 

BioShock - I'm pretty sure I have the digital remaster on XSS and maybe even the X360 digital version as well. I'll have to see if each has their own achievement list and go for anything I don't have. 

Uncharted 2 - I have a PS3 physical copy, but I also have the remastered version digitally on PS4, which came with my system. It might be PS3 because there are other titles here I'll need that system for. 

Orange Box - If I can find a physical copy for 360, I'll play it, but otherwise I'm out of luck digitally on console. 

LittleBigPlanet - I recently picked this up for my PS3 again. It seems the PS3 is the only place you can play it right now. 

Halo 3 - I'll just play it on XSS through the Master Chief Collection like I'm doing now with Halo 2. 

God of War II - This may be another reason for me to break out the PS3 because I only have this as part of the God of War Saga collection. A PS2 copy would be nice though. 

Fallout 3 - I've tried the Fallout series many times but never got hooked on it. Maybe this time? It might even still be on Game Pass. 

Gears of War 2 - Just like previous Gears, I will see about the remaster and the original 360 version digitally on my XSS through Game Pass, or likely that I own them. 

Rock Band - I'm considering reaquiring the instruments I used to have for this but probably just the guitar, which should be easy to get (I saw a bunch of them at Game Junkies last time I was there). Having been an actual musician of sorts, I'm not hugely thrilled with the Rock Band/Guitar Hero gameplay (too rigid and uncreative) but it is a novelty I enjoy - periferal heaven. I believe I'd have to get the 360 physical disc again as well. Probably cheap though. 

Batman Arkham Asylum - I love this game but never finished it. I probably own it digitally too on XSS. It goes on sale (both remastered and 360 versions) so often, I must've picked it up sometime (hard to keep track of the digital collection these days).

Chrono Trigger DS - I remember when this came out. I was so close to picking it up but never did. Now I wish I had. It's going to be likely too pricey to get now. A version is on Steam for PC players, if I was one. Hopefully it'll appear for consoles again. They brought out Chrono Cross already. What gives with CT?

Those are my choices for July. I mean I might pick up Luigi's Mansion 2, Metal Slug Attack Reloaded, and Darkest Dungeon Face Your Failures, but they will likely go on the backlog for now.