I usually prefer TBS, although I play some RTS.
The problem with RTS is that the AI usually just relly on buildings troops faster than you can sending them to war on different front while being able to manage construction at the same time, and the player cannot be everywhere at once.
So it's not really strategy.
In TBS you can actually plan something better. However, I don't like that you have too much control on what happens: attack with unitA, wait for the result, and then attack with unitB if needed. If unitA wins, do something else.
That's why I'm trying to program a game with a different approach.
Each turn, you must give orders to all your units, and you get the result at the end only.
Exemple: in the range attack turn, you have 3 units , 1, 2 and 3. Ennemy has unit A, B, and C, each with a strength of 100.
You may decide that unit 1, 2 and 3 will all fire at unit A. Or that unit 1 and 2 will fire at unit A, and unit 3 at unit C.
And at the end of the turn, it will tell you : Unit 1 killed 60 men, unit 2 killed 45 men, unit 3 killed 32 men.
In you decided to concentrate all your fire on unit A, it is completly destroyed... But unit 1 and 2 would have suffice. However, you can't tell in advance for sure.