Here's what I think is a much improved version of the combat system in Rebellion using only the components that came in the box. For those who don't want the explanation you can skip down to step 1 below the double bars below.
In my view combat in this game is too random. You often draw cards that are useless to you or which aren't in line with why you're launching an attack or when you're attempting to defend against one. This largely deflates bringing in a leader of higher tactics values since the draws are so random.
This alternative adds MUCH more strategic decision making by making card pulls less random while emphasizing the difference that bringing a better leader than your opponent makes.
For those interested in giving me feedback or following more updates as this variant becomes more popular you can check the forums at boardgamegeek
https://boardgamegeek.com/article/23514044#23514044
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Steps are as follows:
1. Divide the 15 combat cards of the theatre (space/ground) you're fighting in into 3 piles of 5 cards each according to the following list and set them close by
Attack Pile
-Deal 1 damage (x2)
-Deal 1 damage to two units
-Deal 2 damage (x2 if space)
-Bombardment (ground)
Defense Pile
-Block 1 (x3)
-Discard 1 card to block 2 (x2)
Advanced Tactics Pile
-Concentrate fire (x2)
-No escape (space)/Escape plan (ground)
-Unstoppable assault
-Brilliant Strategy
2. Each player may draw one card from any pile at the start of combat
3. Compare tactics values. The leader with the higher tactics value gets an additional card or cards
equal to the difference
between his tactic value and that of his opponent from whatever pile he likes (in that theatre)
4. If a shield generator(s) is present, the rebel player may draw one more ground tactics card from any pile for each generator present
5. Proceed with combat as normal except drawing cards is done from the pile of your choosing
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The effect of creating attack/defense/advanced piles
-The key difference is that you now have some ability to target the cards you want and thus to set strategy. For example, if you launched an attack to do damage but didn't score many hits on your initial roll, you can use tactics to draw from the attack deck to try and press the attack. This can grant you more offensive ability but sacrifices your option to try and draw defense/advanced technique cards thus you have a choice
-As more cards are played as the battle progresses you get a clearer picture of the cards left in any pile that can be targeted and thus may want to try and fish for a specific card in a pile. Alternatively, you may take a card from a pile just to try and keep it out of your opponent's hands (i.e. escape plan)
-If your initial roll went well, you may consider drawing from the defense deck instead to help withstand the counterattack
-if you're trying to play defense long enough to retreat, use tactics to draw from the defense pile. You may be able to block enough hits and buy time for your forces to retreat when the turn ends or if playing with no ships in orbit in the ground theatre, you could try to draw Escape Plan from the advanced tactics pile
-seeing what pile your opponent is drawing from can give you a hint at his intentions. If you already have cards from that same pile you can also make an educated guess about what your opponent has in his hand and plan/react accordingly
-need to score 4 hits but only have 4 tactics symbols? Draw from the attack pile and try to get both cards that allow you to do 2 damage to one ship
-did you start off with brilliant strategy? Try to pick up two more cards from the advanced pile to see if you grab combinations like unstoppable assault + concentrate fire
-the one card given at the start represents uncertainty about what your opponent is currently capable of which forces people to consider things like "overkilling" units. It keeps a certain "fog of war" element active
The effect of bringing a better leader
-bringing a better leader than your opponent means drawing more cards then your opponent at the outset which gives you more chances to play them, pay for other cards with them or maybe even just to try and draw cards you don't want to risk your opponent getting from a particular pile. This captures the theme of smarter leaders having more options at their disposal than less skillful ones through more deck control
-when leaders are evenly matched, no additional cards are given at the start of combat apart from the preliminary card for each side which reflects how leaders equal in skill have no inherent advantage over each other and allows a battle to rightfully be more luck-based in those cases
Updates
8/24/16 - Brilliant Strategy - cost to
play
is reduced from 1 tactics symbol to 0
Out of the box it costs two tactics symbols. One to get and one to play and then maybe a third or fourth to actually make use of the cards you draw. Way too expensive and too easy to draw when useless. Not that brilliant really unless you count being able to draw a card in both theatres. By using separated decks and giving it no play cost it becomes something you can try to fish for from the Advanced Tactics deck as a "hail Mary" pass if you're desperate which might let you draw two no-cost block or no-cost attack cards or maybe two Concentrate Fire out of the advanced deck with a good chance of being able to play them right away making this card truly "brilliant".