Some things I've found against rushdown characters like sheik, Cp. Falcon, and lil mac is that they tend to try and bum rush you when you charge your CS. Cp. Falcon especially. Now I may not be an expert in options or frame data and the like. But as an average player I found 2 things useful to use at the start of a match.
I like to start out charging which baits certain characters to do two things. For example lets use one of my favorite match-ups, Cp. Falcon. Most every falcon player expects you to shield cancel your CS, they're first move is to sprint grab your butt and start their Dthrow combos. But because theyre reading either a shield or a roll their totally vulnerable to 2 things you can do while charging.
1. Is pretty obvious, just release early. To some this catches them off guard and followed by a dash attack you'll be landing the first blow and can even combo off that dash. Use early release as a change up too. Remember that your CS is much more than a kill option, its great easy damage, and at kill percents people will expect you to go for a full charge but switch it up and get them staggered enough for a different kill stroke.
2. Is my favorite, grab out of charge. With falcon expecting a roll or shield he's going to try to get in your face asap. Knowing your grab distance and hitting it straight out of charge cancels the charge and gives you a free down throw combo. This will catch 98% of Falcons off guard. The other 2% have a SH approach combo which is punishable with OoS UpB or roll toward center, or spot dodge. I have rarely seen this approach because by charging at the start you seem like a CS spammer who does nothing but charge and shoot, You appear naive.
then its just a matter of using the affore mentioned techniques to mix it up and pull out a win. My experience as the average Joe trying to hold his own out their is that if you make a good play at the start you feel WAY better about your chances. It also throws off your opponent. Most nearly everyone doesnt see option 2 coming. its one of the reasons I win the Cp. Falcon matchup 90% of the time, It gets my rhythm going and disrupts or delays theirs.
We as Samus players revolve around our CS, Either to inflict pain, or to play mind games when we hold it in for ages. Why not use it as bait.
I dont know, just a thought.