Not having the Revised edtion does matter. Nothing released after 2010 is compatiable with the TH 1.0 rules.
I really suggest you get the revised rules $5 for the download (only way to get it; it's not in print seperately anymore).
With that get the equipment cards pack, they greatly speed up setup and pack selection.
Next you should focus on which faction you like most…
Like the Reich, get Hoss…
Like the Union, get Hoax…
If your looking for more maps get Daedalus…
Here is my quick top five, for new players…
Check out the blog for videos on al this stuff, and find me on BBG for even more opinions.
If for some reason your not ready to move to TH 2.0 you're limited to…
All other releases are revised ed. only.
Hope that helps.