What did you use to make the prototype? It looks pretty complete, just do some bug fixes and find an artist to fix up the graphics for you. Most people take much more than a week to do their first game project with no prior experience, so perhaps you have the guts to take this on yourself? \
You are correct. It only looks pretty complete. But it's just a vertical slice of a gameplay - frankly - that is at most 5%-10% of the total effort needed.
I'd wager it's done using gamemaker, since that would be the best tool for the job (e.g. get the core concept to playable state as soon possible - to convey the idea fast).
There's lots of stuff that is missing here :
- a global system that handles data-driven Weapons, Equip, Spells and Potions.
- data-driven stats/rules/tables that can be easily adjusted by level designers (e.g. via text files) without having to endlessly bug the programmer to tweak this/that
- Inventory handling. If you think you can implement a fully-working Inventory system in 2 days, you are in for a drastic surprise, how much actually goes into the "simple" Diablo-style Inventory screen, where each item has different dimensions (thus you need an auto-arrange feature), where the amount of the inventory slots depends on your stats and where, depending on the combination of currently equipped stat-boosters, some equipped items have to be put back to Inventory (which may be a problem if it is full - what happens then ? you want to put it into the world ? maybe you can't, since you are on the ship, travelling between island (and there are 10 more scenarios that the design document usually doesn't take into account) But when you lost that STR+5 necklace, you can't have the INT+3 armour, thus that sword of yours suddenly becomes unavailable and you need to put 5 items into inventory, where anywhere between 0-5 items don't fit
- Special items / enchanting : if the original design document does not have a complete&proven (on paper/excel) ruleset on the generation of the random enchanted items (that auto-adjust to player's stats) before your coder started writing the classes, you are screwed.
- Crate component - how do you fill the stuff ? Based on stats or manually in editor ? How many items can it have ? How many will be enchanted ?
- Persistency - how much of the world is persistent and how much is randomized ? What's your contingency on testing the random component ?
- Combat system - frankly - that should be one the last things to implement for countless reasons.
I could go on like that for few more pages...
To be honest - this is one of those cases, where it is far more important to have a strong game design document from someone who has already designed few RPGs and has direct experience with all the issues that happen in production - thus knows all the corner cases and highlights them in the des.doc so that the coder can take all those non-obvious corner cases into accnt during designing of the classes.
it is paramount that the class design takes all of the above into consideration. Otherwise, it will take way longer to fix....