Any intake will help with doing a Stage1... exhaust, intake, tune. I tend to go cheap and buy whatever SE has that fits.
Same with a STage2.. exhaust, intake, MILD cams, and tune. Basically, it is the exhaust that is the choke point for these types of mods.
Want more power? The heads will need looked after. 110 heads are really a good base set of heads for a head porter to start out with.
So, it depends upon what you will eventually be trying to accomplish. Stage1? Stage2? Stage3up?
Maybe, you need a bit of education? Maybe not. Doing a simple Stage1 or 2? No real need to up the injectors, etc. Hit the heads with some porting, add some compression; big cams? You will be looking for a different Throttle Body, and an intake that fits.
Ummmm.... components of a 'build' really needs to be matched up to gain the best advantages. For example, putting a 55mm Throttle Body on the bike with 6.3 injectors, in and by itself will most likely be terrible to tune and you will not see much, if any improvement. If you add decent cams, and head work, then instead of having too much intake, you would be using and needing that new intake.
An engine is a 'system'. Use a set of components that others have figured out. For best results, don't experiment... don't listen to different folks if they have different build philosophies, etc.
120sq out of your bike is well within reach... the thing you need to think about, first, is HOW DO YOU RIDE THE BIKE? You MUST be truthful to yourself. Most, in their heads, for example, will pick too large a set of cams for their riding style, and when the rubber hits the road they become disillusioned.
So, how do you ride? What would you like to see improved? 90% of folks actually simply wish for a nice Stage2 that gives more grunt down low and tops out about the same. They just do not realize it. Another...say 5%, want in town ripper bikes, they do not 'tour' ever and simply drive around town or close buy. A couple guys, like myself and even Hrdtail78 like touring bikes with some REAL power.... the group that buys 120Rs and S&S 124s.
In ANY improvement you wish to do, if you ever think you will be doing cams? You must think about and buy a tuning device, learn to DIY a tune using a TTS, etc, or... go find a competent tuning shop. You would be surprised how much more you would like your bike with a Simple Stage1 and an excellent tune to finish it off.
Some things to think about.......