To answer your question in-depth: it is something I have thought about, but I've decided with a "no". It's a personal issue more than anything; I haven't really explored post-Gen. 3 Pokemon and the only dragon-esque Pokemon I know about are the Bagon family, Trapinch family, and Swablu family - all of which are pretty Hoenn. I'm supplementing this lack of actual dragon types with dragon-esque Pokemon such as Larvitar, Charizard and Lapras. I figured that since I am going for an old-time Johto feel, I shouldn't add new Pokemon. I am open to reconsidering if enough feedback tells me to think otherwise, however.
The maps made with expanded block data seem to make a huge difference. Perhaps I should also start using Tauwasser's Tileset Extension patch but have been just too lazy to work it out.
For others who did not know: I had planned this to be a strictly Lance-based storyline in which you were named Lance and you had very little choice. But I figured that it'd be more enjoyable if people could forge their own dragon trainer adventures.
I definitely recommend using the tileset extension as it is very straightforward (once you understand the data, and being the pioneer you are I am sure you can!). It allows for extra blocks [suitable for that one before-forest route in Dark Future in which you can have a grassy entrance].
But i would like to ask a couple of things ..Why Kanto isn't available ? And since there are no marts you have to have lots of potions and repels in the wild
To address your Kanto question simply: it's too much work and I had never originally intended to keep Kanto. This hack started out as a simple background story for Lance that eventually evolved into a Dragon trainer's adventure. Like with DarkRisingGirl's issue above, I have a supplement: all Kanto trainer flags will be used in Johto. This means tons of more trainers in a smaller space; this, in turn, means trainers in towns, houses, perhaps even marts.
Speaking of marts.. I am including marts. The only mart that is being shut down is the Goldenrod MegaMart for plot purposes. In all other marts, I will not be including PokeBalls of any sort (I am planning to remove the PokeBalls pocket). PokeBalls will either have to be found in the Wild, or made out of Apricorns which will be highly expensive. I'm also considering making basic items as Potions and Repels a bit more expensive. But most items in the wild will be a combination of frequently used items and pure-money items (nuggets and the like). I never understood the logic behind putting valuable items such as Carbos and Calcium. I am open to reconsideration regarding what kind of items will be found, however.
* Edit: I added another section on the main post regarding feedback. So if you've not seen it yet but would like to say something to improve the hack, go read it! *