SBG: Ways of ensuring reassessment *UPDATED*

I have been trying Standards Based Grading out for a couple years now and really love how much more accurate and constructive my assessment and feedback has become because of it. One part of it that I still haven't managed to get down, though, is ensuring reassessment; the super-motivated students come in to fix their one below-par grade and the ones lagging behind are made to catch up, but everyone else sneaks by without reassessing much and without realising one of the main benefits of SBG (the chance to ever improve on topics done way in the past in class).

In order to remedy this, this year I'm looking to add a few regular methods of reassessment that will feed in to my Gradebook:

• Each week I would like to have at least twenty minutes of a lesson assessing the current topics plus one topic done earlier in the year (If it is a topic that students struggled with the first time around I will give a week's notice and have its revision as homework). I do not want this to be a test every week. More on that later.
• I set homework each week. On week A I will set a normal homework which will feed in to my gradebook (I know that this is risky as I will have no knowledge of how much help that student got, but marking homework is part of the school-wide policy so I might as well count it with the rest). 
• On week B, students can choose a skill they need to improve on and show revision of that topic for their homework. They will get a sheet to help framework this:

• A week before each end of term test, we will have a revision lesson where pupils identify their weaknesses, improve them and reassess. It will be at least a week before so that pupils can revise any skills they still struggle with as final homework.
• UPDATE: Assessed starter/warm-up questions.

I'm think that a test every week would be pretty damn unmotivating for some students, so I would like to mix up the assessments. My ideas for this so far:

• Making a poster to show what they know
• Make an instructional video or presentation
• Make up a difficult question for your partner and answer your partner's question. Grade each other's understanding.
• Marking some questions done by me another student.

As always, any critique or addition to this is most welcome.