One of the toughest things to do in this game is approach against a skilled player, especially if you are working against the clock as well. We see aggression at the highest level, but even then it isn't blind and the very best player plays an interesting hybrid style. With shiek, you can force everyone to approach for multiple reasons. Needles win pretty much every projectile war, even shutting down projectile characters like duck hunt dog and megaman. She has confirms for the first 50% or so, which means you will usually take the lead unless you somehow don't land a fair and get beat up badly before then. She also has kills from both grabs and neutral tools (such as weak hit nair to bouncing fish kill confirm) so the chance of getting the first stock can be moved in your favor if you aren't fighting a character with similar abilities. The characters with confirms aren't as good in neutral, and those competitive in neutral aren't as good at confirming, with few exceptions. These are the top tiers. So shiek has the answers, but it is up to the player to put it together.
So you are playing against someone trying to put this together better than you with their tools. Thats the true challenge of fighting games, as all of your tools ideally have counterplay. With anyone, you have to make some sort of good play to get a kill. Sure shiek makes them approach and has easier methods to set up the kill, but in exchange she is relatively delicate. Also, everyone knows how to play the MU because their scene has a good shiek. Pika is a really difficult character, but as you get to a certain level you benefit from people having no idea how to deal with your tools. You still see ESAM drop below the stage and top level players walk up and look over the edge like dodo birds while they get hit with a thunderbolt. So in that way Pika's tools have an advantage, though they may not be as good as shieks.
Then we have ZSS and Ryu type characters where they kill so fast, you only have to read the opponent less to win the game. Optimization of combo and advantage game lets you net wins before the opponent gets their skill geared up and before they start reading you well. Some people might find this easier.
And thats the point. Find a set of tools which benefits you the most, whether that be through winning or through having a good time. Don't worry yourself with who is having an easier time doing what, because we don't have a true measure of how difficult something is. Because in the end, if you are competing, everyone should be applying the same amount of effort: all that they have.
