No right answer, really. I use 3D for 2.5D gameplay because I'm better at skinning models and animating bones than drawing hundreds or even thousands of 2D sprites. Depends on what you and/or your artists are faster at. There are plenty of games with great hand-painted or cartoonish 3d models.
Besides, you HAVE TO visit that little planet at least once to check if there is an enemy, or if there is some wormhole or anything. So, making scout ships expensive would not solve anything really (plus then you would send cheap frigates or whatever you have).
That's exactly it. Scout ships should be neither cheap nor expensive. There's a middle ground where you should debate whether it's worth spending a few turns to build one on a new planet, or one or two turns on a productive one.
Never make players wait to do what they want in a menu. It's super annoying and no game I know does this.
That said, the article isn't especially clear. If you got to the exit option through a menu, you don't need to do anything else. You've already pressed at least one button earlier to get to the exit. That's all the warning you need. However, if your game is in windowed mode and there's a chance that you can accidentally click on the X at the top right corner (or wherever), definitely feel free to put in a quick "are you sure" confirmation. But only for that specific case - not for the menu navigation.
Consider also that you may have the answer right in your post: your friends. If your friends didn't enjoy some of the games you created, why not ask or, even better, brainstorm with them about what you would all enjoy playing?
You're definitely good on timing. Try it for yourself, for fun, and see how you do. Just the usual two important things:
1. Start simple! Make a number guessing game. A pong game. Whatever. But definitely start small.
2. Know that it will take a while. You can learn a programming language like C++ as most people do but you can also make games with game making programs where you don't even need to code. (The tradeoff is that you have less control over things but usually this is ok for beginners.)
Look around this site for beginner articles and it's also worth starting here:
I gave up on it very shortly after I tried it. I tried to make a platformer and the character couldn't jump half the time while it was on a platform moving down (as I'm sure the system detected that it was in the air, even if it looked like it was just standing on the platform). It also got glitchy when you tried to mix in physics with the character controller. This could easily involve some lack of knowledge on my part but it wasn't a very encouraging start.
According to their monthly survey, a third of all Steam users use 1920x1080 (increasing). Second is 1366x768 with 23.87% (increasing at half the rate). Whatever resolution you pick, make sure your support for those two is strong. I would personally use the first and scale down from there. Tile size, as everyone else is saying, is less of an issue. You can quickly make a mockup screen for each scenario (check this out as an example).
I suggest watching some Guacamelee gameplay videos. It's not swordfighting but it will give you a good idea on how decent animated 2D fighting looks. Notice that almost the entire frame changes every time. Dragon's Crown is another good example (here's the Fighter video, with sword). I know you don't have a team of artists at your command so you can only do so much but the more you animate properly, the better the game will feel, automatically. Also keep things in mind like characters being pushed back a little from damage and damage effects (like what Street Fighter also does).
Also, there are some decent animation tutorials on line if you're interested. Stuff like this. Google around to get some tips.
So you know, you don't need to know 3D math to create 3D games. Many engines like Leadwerks, Esenthel, Irrlicht, etc. don't require it and have functions to make your life easier (like calculating the distance between two 3D points for you via a simple function).
If your goal is really just to use graphics engines then I think you're doing more than you need to. For example, I use Leadwerks. Check out sample C++ code here which shows how to set up a scene, load a model and display it. If you understand that then you can make 3D games with it. Other engines are similar.
To be honest, you don't even need a language to start. There are good game makers out there like Construct 2 where you can start off with just changing settings and only later adding code whenever you feel it necessary.
That said, feel free to learn a language (I would suggest C++) if you really do have a lot of time on your hands.