Me and a friend did some testing of the features available to see if we can use this for our DnD every week since people are scattered now with school done.
Thinking about what it has so far, here is what I would like to see that if they were there, would make me willing to pay for this program.
(note: Some have been mentioned before, I am just putting everything I can think of/want in a list)
Groups:
This is on the list for future implementation. Will be nice to split people into different screens at times.
Fog of War:
This, while nice, I think needs some work.
1) Currently, if the characters move to a screen and you set the option to place FOW after they view it, it will not show up.
2) Player based FOW. Not every player should see around a corner just because another player does. Allows for characters to tricks others etc.
3) GM FOW view. When using a darker background, its impossible to tell what you have revealed. Adding options for opacity and color similar to the grid would help.
4) Better revealing. Allow free form (mentioned in another post) and I think grid reveal as well as in click squares/hex to reveal that section.
Player Controls:
1) I believe that the play should have the ability to create their own character and edit it themselves, not the GM for everything and only allowing chat access.
2) Players should have better access to their tokens, like health/auras so that they can activate their own aura when used and take away health. If players are abusing this, at least the option to allow access should be added.
Shortcut Keys:
Extensive shortcut keys for options.
Drawing/Freeform:
1) Color control should pop up when selected, not after drawing.
2) Addition options as seen fit (shapes, tools etc, not a big thing, but nice just the same).
Status Affects/Damage:
Selecting multiple tokens only allows you to edit one, it would make it easier to mass edit tokens. For example, a wizard cast fireball dealing 17 damage to 10 targets in a large battle, selecting all tokens and typing "-17" would be much easier than doing each one by itself. Same goes with effect markers.
Range/Measure type options:
While the current measure is lacking a bit (which is on the road map to be improved), a nice addition if not planned is AOE markers. For example a spell with a 15 foot cone range, it would be nice to allow a overlay visually showing what the cone looks like on the map and what it can hit. These could act similar to tokens.
Markers:
Going off what was said in the Range/Measure option, it would be nice to have a marker layer in addition to the current three(background, token, GM). In these layer, things such as the AOE markers, new terrain markers, etc could be placed over the map with a opacity option to better outline certain things over time. Players could have minimal access to this layer.
Turn Order:
Possible option to allow players to have no token access when their token is not the current selected. I know falls into a more specific option that may be against the design course for the developers, so it should be a additional option only if done.
Chat:
A nice feature would be to re size/re-position chat for people.
"Player Character Sheets" (longer read)
Now before you start to think that this is against what this program is suppose to be, hear me out on this first. I will try to explain this the best I can from both sides (as I don't know their system layout/coding language) as this would be the biggest task for things I would like added.
In the character edit section, you can have a "character sheet" and I use this term loosely as nothing is predefined. When making a sheet it starts blank and you would select a "add field" option or something similar. From this, you enter a field name, tag (explained in a bit), value, description, and possibly type (if desired, explained later). Lets put this into an example for BAB.
Name: Base Attack Bonus, Tag: BAB, Value: 3, Desc: added bonus to attacks, Type: Modifier.
Now that we would have a BAB field in the character sheet section on a given character, we can view it at any time (allowing central management of characters) but we can use this in rolls. If we have a character with a name of Ladreth and we wish to set up an attack roll macro, we would type something like /r 1d20+Ladreth:BAB+Ladreth:STR:mod. This example assumes we have set up a STR field similar to BAB (ex: Name: Strength, Tag: STR, Value 14, Desc character str, Type: Stat)
Now lets go over this a bit more. 1d20 (same) + Ladreth:BAB (This references the field with the tag BAB from character Ladreth and adds it to the roll) + Ladreth:STR:mod (this one is similar at first, get value of field with tag STR from the character Ladreth, but has the mod option. This applies an possible use for the type option of a field where is auto calculates the mod value since it is of type stat). Later, if a field value is updated, the macro is automatically updated since it is only a reference, not a "hard coded" value, so updates are only needed in the "character sheet".
Example for a Skill field(Name: Hide, Tag: hide, Value: 7 (alternative macro value: 4 + Ladreth:Dex:mod), Desc: Mod to hide checks, Type: Skill)
So for implementing, you would need to have adding in macros for rolls to access the DB used for the campaign and get the relevant value. The tag entry could be used in the code additional for checks (again, no idea of your code, but similar to html/JS tags for field values).
Now how does this not impose more rules and take away from the freedom of the system? As explained, everything is a simple field with a name, tag, value, desc, and type. Nothing about this imposes any rules onto characters, it only adds to the ease of having the values at hand and for quick reference in chat, rolls, macros, quick DM check for the character, etc. All fields can be used as the GM/players wish for their system, not just one system. One thing that is grey area with this is the type option, though it could be left out and done later with user define types (a lot more work).
May think of a few other small things, but this is what comes to mind at this time. However, if all these features were in, I would have no problem dropping money for this program/buying assets from roll20 to help support you as much as possible.