The following were my results on my '14 Ultra Limited with an Arlen Ness Bigsucker Air Cleaner, Power Commander V and a custom dynotune:

 

Also make sure the 2 into 1 exhaust you choose will be able to handle your future builds. You don`t want to buy an exhaust twice

 

This was going to be my next advise... It may be difficult to lay out a "final condition" of the motor, and piece it together over a couple years. You'll find most likely that some of the pieces don't really work well together, unless condition 'X' has been attained, and you may wind up very disappointed in performance during the journey, till you get all the pieces that are supposed to work together well.... actually together.

My advise: create a kitty jar to put your extra money & change into. When you have the funds for your 'end condition' pipes, drop the money into the jar.. same for your other parts. When you have the funds to buy everything you need at the same time, then you pull the trigger.

 

What is the goal? Work towards that goal. Then of course as with any project the goal may change as you get into it.

1. Ride
2. Ride some more
3. Keep a small pad and pen in your vest/jacket/bag. Take the time to note what type of riding you actually do. Where is the rpm, speed, road type, miles, etc.
4. Invest in a good exhaust (2:1 is best for power and tuning/ some of them suck but they look cool, research the difference, 2:2 sounds bad *** but may lack in best overall performance), A cam for your type of riding (cam choices are endless and everyone has an opinion. There is no magic cam. Look around for what works for your setup and talk to your tuner. They see tons of setups and can usually steer you in the right direction. DON'T believe dyno charts you see posted by cam manufacturers as a general rule/ , and decent tuning software. ( Power vision and Thundermax are about as good as its gets. IMO a Power Vision license from a shop that has PV capability is most economical and best route. ) Get custom mapped tune. Stage 1 air cleaner ( this doesn't have to cost $400 BTW)
5. Ride !
6. Always have good tires and brakes.
7. Ride more
8.Ride
9.Yep
10. If after this you still want more. Go larger on cubic inches and THEN do heads and throttle body etc.

I have many customers that stop after cams ,exhaust, air cleaner and tune as they feel the bike does what they want. Others spend a ton on the bike to boost performance IE: slap on the latest rage parts but don't actually ride enough per year to warrant an oil change. Ride !

 

 

You REALLY WANT TO IMPROVE?
Forget throwing money at your bike for now. How about investing in YOURSELF?
Take an advanced class.
Take a curcuit class.
Take "Bike Bonding."
Take "Ultimate Bike Bonding."
Then, come back here and we'll figure out ways to drain your bank acct!

 

Take a look at the ThunderMax for a tuner. It can self tune, no piggyback computer, and comes with wideband O2 sensors.

 

My first upgrades were Rinehart Slip-ons, Arlen ness big sucker and VH FP 3 tuner. Been very happy thus far.

Next upgrades will be rear and front shocks come spring. Thinking about going with the Legend series A's for the rear shocks. Gotta save up for them though.

 

Dynojet Power Vision from Fuel Moto. - Jamie will help you along the way as you do mods with ballpark maps and advice.
The Autotune basic (stock O2 sensors) has worked very well for me to refine the initial map I go from FM

 

It sounds like you want a basic stage 1 with the ability to do more later. And I think this is about how everyone starts off.
Air cleaner - take your pick
2:1 exhaust - thunderheader is generally referred to as the gold standard in this category
tuner - a lot of guys like the v&h fp3. I have one of the original SERT tuners, and have no clue how to use it. This will depend on your experience level and needs.

These mods will give you a modest but noticeable difference over stock. Try it out, play around, and if you want to, you can still go bigger.

I noticed you said more cubes and cams down the road. My recommendation is to do both of these together. While you certainly can do one without the other, it's easier to tear down a motor once instead of twice.

Investing in a decent tuner and 2:1 now will keep you from reinvesting in them when/if you go from stage 1 to stage 3.