"However, I wanted to be able to develop Wesnoth quickly, using the latest technology and latest C++ features. Because of this I didn't spend much time focusing on things like minimizing the memory Wesnoth takes up, or trying to make it ultra-fast. This does limit its portability a little in that it is difficult to get working on systems with limited memory"
Honestly I think it could be written in Javascript with better results than it currently has. I've never tried multiplayer as I found the single player laggy which is unacceptable for a game a "simple" as this. Just goes to show that language alone doesn't alway influence speed...
This game isn't exactly simple. There's an entire meta language called WML (Wesnoth Markup Language), support for a powerful AI and Lua scripting. There's also very intricate multiplayer code that I don't think in any way could be trivial with JS.
Yes, Wesnoth is hamstrung a little by its tech stack. The dev team very much wants to move to SDL 2 and support OpenGL in the future.
How will they do that? With more and interested developers. Hence, the call to action.
Why don't you just stabilize everything and prepare to release a final polished version? Then, you can decide if you want to keep working, or if you want to stop and put the game in maintenance mode. Do you even have enough developers to support that? There is value in completing creative projects.
"However, I wanted to be able to develop Wesnoth quickly, using the latest technology and latest C++ features. Because of this I didn't spend much time focusing on things like minimizing the memory Wesnoth takes up, or trying to make it ultra-fast. This does limit its portability a little in that it is difficult to get working on systems with limited memory"