As for your popfile, popfiles are my favourite part of any MvM map because they offer so many different options, my general advice is just run with whatever ideas you think are cool for implementation, and from there tweak and buff/nerf based on player feedback.
I probably will be the one to make his popfiles
. and difficulty wont realy be a problem for hard waves. (easier waves is going to be an issue as im a bit of a giant spammer - but even that shouldnt be a problem)
Anyway, to add some information and tips.
Size
Where decoy and coaltown are relatively short in the length most newer maps are long. Those short maps although they are still fun have the problem that you cant realy put in strong classes as there is barely any time to realy catch up and go back to the front. While in long maps it can be done very well. So for the size i would at least go for mannworks as length. Where i made a short map i notice that once you have a few waves, you kinda forced it to the maximum already. The only way that you can make it harder is to add stronger classes. And thats why the later waves on skullcove are mostly giant spam (still, with these new ones that also is covered these days by allowing alot of variation).
The intro
This is realy the only image people will remember of your map since they will be looking at this for most of the time. Make this look interesting to let people remember a map.
The bombsite
Again a keypoint as similar to the intro, people will see this alot aswel. So this area should have something that makes it feel unique, even if its just the gameplay on it.
Both the intro and bombsite matter, if neither of them is unique people will forget the map. They are most important into looking unique. People can remember a map just by specific small features:
A huge canyon (decoy - note, even mannhattan has ones but im quite sure its not the part people remember it for)
Lowered bombsite and deathpits (coaltown)
Wide map with 2 paths (mannworks)
Long map and cave (bigrock)
Old town, wooden defence (Rottenburg) - i kept the forward spawn out as later maps are very likely to kill that argument
Banana peel (mannhattan) - for its looks i dont have any other good part that makes it stand out. it looks dull to me.
Pathing
Allmost all maps feature at least 2 paths. Many times with 4 flanks at the end. However, barely any of them actualy do it the same:
- Decoy has 1 main path, a side path, and a side flank as main paths. But nothing realy special to that
- Coaltown is 2 paths and 2 flanks, again, nothing special
- Mannworks has 2 paths that are completely seperate but no flanks. This is diffirent as its actualy the first map to feature 2 completely diffirent paths. However, rottenburg has been added as a map of this kind except even then it varies.
- Bigrock was the first truly long map. This showed waves which are alot harder just because of stronger and more giants. This showed a very positive change to the way of playing mvm. However, since the tunnel proved just 1 path its bad on that. Its easy to bottleneck.
- Mannhattan is the first with control points. Although it only has 1 path for most of the map its still a 2 to 3 pathing system. As its a bomber path, or capper path.
- Rottenburg to me is a mix of mannworks and bigrock. It features the same bottleneck as bigrock and most of the combat will take place there. To me this is quite bad since most of the map will barely get used. This while its just like mannworks having 2 completely seperate paths. Its a waste on that.
Remain unique
What people remember is systems that make it not feel generic. This will make your map stand out. Even if you want to make it feel generic have something that people will remember. This can be an area with something over the top in looks, or something with over the top gameplay. Mannhattan has its capture points for this at the moment.
Think before you build
Dont allways think that special is better. Yes, a payload idea for bots might sound like original and fun. To remind that it focusses them to a very small area and this means spam has become easy. Avoid it.
You are going to detail a map? What is the theme going to be? Does it fit with what i created.
Originaly skullcove had the idea in an aztec theme. However, the idea that i suddenly had was 'Hmm, what if i make it halloween and do this and that'. One of the ideas was to have thunder in the map, rain and such. I scrapped that idea of rain instantly. FPS was important, rain is a hell. Thunder remained as an idea but without other ideas it wouldnt work. It in the end took me 1 week to decide what i could do:
'That reset zone could have a nice view over a black ocean'
'What if i put the skull close into the map'
'What if i make a nice church in the back'
'Those 2 towers in the middle can be nice in those halloween styled ones'
'What if i make the deathpit long and similar to the lakeside one'
These 4 ideas did reach the map and were mainly what i started building on. And not even all those ideas reached the end (2 towers removed, deathpit was alot shorter)
However, if i would describe my map on its uniqueness then probably the only realy noticed thing is the skull. A thing that i should have done better (although im still happy with the final result since in my case it was mostly focussed on gameplay - and im quite sure that many have remembered the chaos)