SmashChu, as much as I share your stigma against the smash community, please stop making "Serlin" (SIRLIN ...) and yourself look bad. Reread the book he wrote (lol "when he made up Play to Win") and find the part where he talks about when playing to win results in degenerate play. His solution to simply play a different game, because a game where the winning move causes the game to be degenerate -- that is to say, uninteresting -- is, by his definition, a bad game.
Also, your comparisons to Starcraft don't make any sense as Starcraft is not a fighting game. Yes, it's another competitive game, and we can, as you say, learn a lot from their communities and game design. However, your claim that combos are not needed because Starcraft does not have them is the logical equivalent of saying "hitstun is not needed because Starcraft doesn't have any." Or "Smash needs resource management."
This just shows your utter misunderstanding of what combos actually do as a game mechanic. At the beginning of the combo, we have the combo starter. In theory, the combo starter is really just a very powerful attack. After it starts, the player must make a correct evaluation in order maximize damage. He must confirm the starter has hit, in some cases must determine what kind of hit, then choose the most damaging options afterward, which may change based on factors like stage position, or game specific things like distance to a wall or edge, DI, or combo-breakers like GG's burst. The interaction is mostly one-player, with the comboing player making most of the decisions.
So, without comboing, you lose some key things:
-Some powerful options. Most of the time, combos will offer more damage than single hits, so losing powerful options decreases the impact of any single choice in the game. This is easily replaced by having good single hits, but Brawl does not have them. For this reason, almost all single choices in Brawl have little to no meaning, and one gains very little ground for each correct prediction.
In a smash game, where there are so many options, a correct read should mean a great deal. Since it does not, lack of true combos DOES hurt Brawl in this way.
-A valuation test. The combo tests the comboing player to see if they can maximize damage, or optimize the situation. Yes, once you go on the community site and memorize a combo in most fighting games, you don't have to vary it up. However, this situation optimization is no different than knowing not to spam charged smashes. The combo mechanic just adds another avenue for players to excel in the valuation test, the test of game knowledge and optimization.
Without this layer of complexity, Brawl is less deep is therefore hurt by lack of combos. In case you're not convinced that valuation is a necessary and interesting skill test in order for a game to be good for competition, consider a single game of rock-paper-scissors, where no valuation is done. Single-round rock-paper-scissors is a terrible competitive game because it tests prediction without valuation.
-An execution test. All non-turn based games test execution to some degree. This test can infuse some of real-life's depth into the game. However, sometimes the execution test is uninteresting. When no choice is involved, the execution test is said by many to be "arbitrary," but when valuation or prediction is tied with it, execution becomes interesting. (Consider a button mashing Mario Party mini-game and professional sports. Which is more interesting?) In most fighting games, the combo mechanic involves little choice after the starter, and therefore little tie to valuation and prediction tests, but in Melee, the interaction is two-player and is moderately tested by prediction and HEAVILY tested by valuation, thanks to the added complexity of varied knockback due to percentage, different hitboxes at different times in each move, stale moves, and DI. Having to make decisions based on a complex system and executing it on the fly makes for very deep and therefore interesting play. The execution test must be high in order to allow for many decisions to be available in real time. Not having the execution test on its own does not hurt Brawl much, but its tie to the other interesting skill tests is too strong for it to be "arbitrary."
Melee's combo system is the deepest ever conceived, and Brawl could have had something similar. It does not, and it loses depth, therefore lack of it hurts Brawl.
As usual, my analysis seems pretty comprehensive to me. Let me know if I missed anything, but for the love of god please do not restate anything.
Sources - recommended to all
Kiekegaard, Alex. On Complexity, Depth, and Skill
http://insomnia.ac/commentary/on_complexity_depth_and_skill/
Sirlin, David. Playing to Win.
http://www.sirlin.net/ptw/