Right now, as designed, HOI3 is a sandbox game. Sandbox games will appeal to a certain percentage of the people who play the game. The game mechanics are getting really close to working correctly, and the game is playable. Yes, there are some issues, but 1.3 seems to have gotten us to the point where what is left is much more 'tweaking' things than the base underlying fundamentals that are the issues.
For those who like historical play, it is much easier to corral a sandbox game - especially one whose coding allows scripting as this one does - than open up a game that depends on the historical scripts for game balance. Once the community, or PI itself, put their minds to it, a very historical (well, as historical as HOI2 most likely) will come out.
I'm looking at the mechanics of the game, etc. to see how they are working. So far, most of the big problems seem to either have been solved or are on their way to being solved. One great thing about this game - if you don't like something, you can change it yourself. Don't like SU's manpower? Just put in something that gives them more. Don't like the techs that Japan starts with? Just give them the ones you think they should have. Where else is there as open a system?
If you look at the list of what people considered 'game-breakers' from 1.2, how many of those actually got solved in 1.3? Yes, there are some that have not, and it seems to be a personal thing as to whether your pet peeve issue got corrected as to whether you like 1.3 or not. If it didn't, then you're seeing it here on the forums in negative posts. If it did, then you are seeing it here on the forums in positive posts. There's a third set - those who are watching this as a great work in progress, who are happy digging into things and watching how things work and trying to figure out why the AI is doing/is able to do what it is doing.
Yes, I think there are still some problems with 1.3. Yes, I would love for the things I look at to be corrected at some point in the near future. Is it playable as a sandbox game right now? Yep. Are there issues at times? Yep. (No Eastern invasion because of a huge stack in Cherbourg facing off against a huge stack in the Channel Islands that has happened about 5% of the time for me so far is an issue).
I must say though, that I am someone who saves often, and will purposely go back and re-load saved games to see the alternative outcomes based on certain positions. I don't have any performance issues at this point (if I let the game run hands off, I am still at about 7 secs a day in 1942 in the heart of the world at war.) I have many different starting files saved (yes, I went in and altered the org structure a couple of times and saved them down as different builds - I can just go in to one of those that is closest to what I want to do this time and start with most of the work already done.)
So, for those who are looking for WWII, I would bet good money that it will be here. For those who are thinking that there are things that are very broken, figure out if that's something that is broken in underlying concept or if it is something that can be fixed with a quick cheat or change to the original OOB (i.e. Soviet Manpower). If it's the former, then that is something that needs to be addressed with patches, etc. If it's the latter, then do what you want, and suggest it as something that could be changed to be more realistic, game-balancing, etc.