There are much better options than what HD offers as "kits", and then there is always the part about dealing with questionable technicians at any given HD dealership. And regardless of what your dealer tells you, your warranty is chit with anyone else but them, and even then it would be highly questionable if a big problem occurs. And I guarantee you they will not put any of it in writing, as Don mentioned above.
Big HP numbers are fun if you are in the habit of winding the motor up to the 6,000 RPM range a lot. Big Torque numbers are a lot more fun, especially in the 2500 to 4500 RPM range, where 90% of typical riding happens. There are several ways of getting where you want to be, and the $$$$ amounts will vary as much as the variety of combinations.
In all probability, by the time all is said and done, you will have as much or more in modifying the 110 as you would in just buying a complete motor like an S&S, or even the HD 120R, which, with just a minor tweak or two would probably get you the same end result. Then you can shelve the 110, or sell it and recoup some of the expense. And probably have a more reliable package in the process. Plus, if you ever want to sell the bike, you can stick the stock motor and parts back in and get true book value.
Either way, if you do more than pipes and a good tune, your warranty is not worth the paper it's written on...even then, it can be suspect if the MOCO decides to be a hard ass. Technically, ANY modification to the engine and drive train CAN void the warranty, but they are much less likely to take action with just pipes and a tune.
There are several people on here who are much more knowledgeable with regards to S&S options available in crate engines, or tweaks to the HD 120R.