On Saturday, we're launching the feature where you can control which parts (writing, tone, definition, reading) you study for each list. You still have the master setting in your account settings, but then in each list's settings, you can override the master.
It hasn't seen a ton of testing, so if you're interested, please roll over to beta.skritter.com, give it a shot, see how well it works, and let us know if there are any bugs before we launch it. Thanks!
Scott also just added a checkbox in the list study settings to toggle whether you want to study writings and tones for any sentences that are in the list, so if you really want to write out sentences, you now can do so again.