Sly 2 was just meh because it suffered that AC1 effect to where the game was a good length but you pretty much just find yourself literally doing the same exact mission formula over and over again with each world you entered. The only diversity were the boss battles and evirmonments. Sly 3 was similar, but it had the added features of having a diversity of missions in each world and new characters to play as. Honestly Sly 3 is by far my personal favorite in the series.

if you are close to platinum finish platinum.
i won't try (i already have all collectibles and liked collecting them)because i know i'd forget to activate the map here and there and i 'm not willing to play the whole game 3 more times for this trophy.

btw-i'm feeling free to ask you wether you finished all captain quark 2.5 D games(got the trophies) in Ratchet and clank HD(one time limit was really so annoying that i gave up trying to get platinum)

If you're getting (or already have) a PS4, the Minecraft on PS4 idea is brilliant. It'll be a lot better, I'm guessing you won't have the limited worlds you have on PS3 and X360. Other than that, I'm not sure there's going to be much difference... But I think that alone is the reason I haven't bought it on PS3 in addition to PC.

If you're not planning to get a PS4, you should probably finish the platinum if you're close and then get Minecraft. If it's still a long way to platinum, get Minecraft if you feel it interests you enough.