Bad idea.
1.5 runs ALL homebrew. Check out Fanjita's list of compatible homebrew to see if any of it applies to you.
As for web browser, it sounds nice, but why bother? My cell phone has access almost everywhere.
GTA LCS is another thing I don't really care about. GTA has been done 3 times prior to this game in 3D, and I doubt LCS can really compare to its PS2 originals.
Yes, you can downgrade back to 1.5 if you don't like 2.0, so go ahead an give it a shot...
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