Here is one way to look at it.
As for what bike think long and hard about what you know your going to do with it and what you would like to do with. Find the model that can do it best for you. They almost all feel great when you sit on the in the show room and they all feel bigger than they are.
Forgo any mods to the bike you do not have to have to make the bike fit you. I will try to list some reasons.
1. financing mods can quickly make an affordable bike not.
2. Mods do not add to the value of the bike. Should you find it is not the bike for you down the road all cash spent on mods it just about lost.
3. You said first HD. Well you have a big learning curve coming, every time you think you have it figured out, more options and ideas will becoming at you. Take the time to fully understand what your doing to it and why.
Example buying pipes you latter find to loud to quiet not the look you wanted is expensive.
You only really going to learn most of this by getting out there and riding it around other HD's
4. It is just way to easy to go nuts in the Hd toy store.
5. doing your mods slowly of time keeps the bike fresh if you do a lot at once you have to spend even more to get the same joy from changing it.
6. While I buy 90% of everything for my Hd's from a dealer not everyone does you may wish to buy some were else. If you do buy from the dealer if you do it all the day you get the bike ,there you go out the door. If you pick up a part for mods here and there from dealer you build a relationship with them. Dealers treat customers they have a steady relationship with better.
As always your ride your cash your call.
Enjoy the ride