I'm finding it really tricky to edit my piano recordings in midi.

I can do something like 20-30 takes to get it perfect, or as close to perfect as possible, but making tiny touches and getting the velocity, off notes and smooth broken chords through editing seems impossible.

The thing is my playing accuracy is terrible, and making countless takes is still easier than midi editing, I feel like I'm doing it wrong.

Also how to I mimick my pianos sustain pedal if inserting new notes? I tend to hit sustained chords with melodies or bouncy ragtime chords and I cant figure out how to add sustain manually to notes I insert or move.

In my experience, re-recording a live performance until it's as good as you can get it is always preferable to editing, especially when it comes to velocity and duration (including sustains). Not only because it will usually save time overall, but because it generally yields more "lifelike" results and gives you practice that will make future performances better.
 
Adding sustain manually can be really challenging. In some cases, it may be better to just increase the duration of notes as though you held them. But in general, I'll say that it's common for the sustain pedal to go down right after a chord is played (while the notes are still held), and come up right before the next chord so that changes don't overlap. So you end up with pairs of up-down pedal events that are close together, often on either side of a bar line.
 
It's hard to advise without seeing exactly what the performance looks like.

That's how it seems, I've had plenty of practice but my accuracy has always been terrible and never improves.

I don't know which version of Sonar you're using since you have nothing in your footnotes.  But, editing in PRV in X3 is not so hard using the smart tool.  Note durations and velocity can quickly be edited en masse or individually.  It only takes a little time to watch some of CW's videos to get the picture.  Best of luck.

     In the prv view, you can show controller lanes underneath the notes. One of these controllers ( CC 6 I think) shows when the sustain is depressed or released. Using the DRAW tool (from the hud ), you can add sustain pedal up or down at the appropriate time. Small triangles appear as you do so. To open the controller lane, press on the little plus sign at the left of the lanes eg in the volume controller lane.
    As regards timing, if you can get close enough , have you ever tried quantizing ? This will move selected notes to the nearest point on a  grid to a resolution of your specification . Sometimes this has worked for me , but it can make things worse if you're way out. I usually have to play something several times before going to work with quantize and editing in the prv.
   And another thing I do is set the project to a slightly slower tempo whist I record to give myself a better chance to be accurate, before reverting to the correct tempo. 
 
 

Yes I already tried quantizing individual notes that were slightly off, but trying to touch up and perfect just a small 2-4 bar recording was taking me far too longer than just doing lots of takes.

I'm using Sonar X3.

    When I quantize, I don't select individual notes. I select a group, or all of them ( by pressing Ctrl and A ). So in your example, I would select all the notes in the 2-4 bars, hit quantize, and listen to the results. You can press undo if the result is unsatisfactory.  Usually I will find most of the notes go to the right time, and those that don't I move manually. You could try a very fine resolution so the notes don't move much at all  e.g 1/32, or experiment with coarser resolutions until improvements ( hopefully ! )  arrive. But I have to say if the original timing is too far out results will be unsatisfactory.

Here's a quick reference to MIDI edting:
http://www.cakewalk.com/Documentation/default.aspx?Doc=SONAR X2&Lang=EN&Req=Tools.23.html#1234205
 
In particular, you may want to give "To drag-quantize MIDI notes" a try.   Done in groups, it's a real-time way to see how the notes will be shifted.
 

Stephen@thesummerhouse
    When I quantize, I don't select individual notes. I select a group, or all of them ( by pressing Ctrl and A ). So in your example, I would select all the notes in the 2-4 bars, hit quantize, and listen to the results. You can press undo if the result is unsatisfactory.  Usually I will find most of the notes go to the right time, and those that don't I move manually. You could try a very fine resolution so the notes don't move much at all  e.g 1/32, or experiment with coarser resolutions until improvements ( hopefully ! )  arrive. But I have to say if the original timing is too far out results will be unsatisfactory.

I only needed to edit one note that was slightly off time in that case. When I tried quantizing everything, it got ruined too much as I use a lot of split chords and off time notes.

Vab
Yes I already tried quantizing individual notes that were slightly off, but trying to touch up and perfect just a small 2-4 bar recording was taking me far too longer than just doing lots of takes.

I'm using Sonar X3.

Yes, using the computing power of the human nervous system can be far more efficient than software. But as you note, humans are subject to errors that render the product less than perfect. The power of software is that it has a very low error rate while doing enormous amounts of similar well defined calculations. If you want a high level of control over each individual note after it is recorded, it is going to be somewhat tedious. Ironically, something like pitch shifting a whole song, although it requires monstrous math manipulation, is faster to achieve than setting the note duration manually for every midi note. What you are doing is like asking your word processor to replace every word in your book with a word that works better in the context. You can avoid a lot of retyping by using the word processor, but you still need to find the clumsy words and choose a better one.