The R&G bar ends won't do very much... They absorb a little impact, is all. I presume you've got crash bungs already? Swingarm bungs are OK, mine have certainly done some good, though I don't know how much. The R&G can protector is quite good, if completely ugly- I did have one but it didn't fit well with my system, and came loose all the time.
Other things you can do... rearsets with solid pegs give a good bit of sacrificial protection, as well as keeping the bike more rideable after a crash- you're far less likely to break a rear lever or hole an engine case.
If you want to take it a bit further, Engine Armour do Kevlar or carbon fibre engine and clutch casing covers... Or alternatively, Woodcraft and Vortex, among others, make metal clutch covers, decreases the chance of holing the plastic one and filling your engine with gravel (not that likely, mind) You can see these on the JHS Racing website. A Baglux tank bag gives some tank protection. You could fit crash bars, if you're desperate
If you fit all that stuff... Well, it'd be cheaper to crash it and fix it