Hi
Mike
Here's a few comments that may or may not be of help to you. Of course they come with the preface that these are my opinions and don't necessarily carry any more weight than anyone elses

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The hamon is hard to see in the photo's but I would say that for aesthetics you need to work on getting a more sharply defined edge to it and for it not to extend too far 'up' the side of the blade. Half way to the shinogi (the 'waist' or ridge-line of the sword) is more than enough. Of course, the pattern of the hamon affects this proportion quite a lot. A straight hamon should not extend as far up as, say, a peaked 'long wave' design.
The seppa should be larger than the fuchi (base) of the tsuka but not so large as to overhang the centre of the tsuba. Overhanging seppa look a bit untidy and can be seen as 'cheap' in that the parts used were what were on hand rather than what fits. If you think you can recreate the edge pattern of your seppa there's nothing to stop you filing it down a little.
It's again hard to tell from the pictures but the tsuka looks somewhat short and the bottom is too 'fat' compared to the top, at the same time being a bit 'high-waisted'. The tsuka should be about a quarter of the length of the sword (this can vary widely from school to school mind you) and ideally when wrapped with ito should match the girth of the saya. It should have a sort of hour-glass profile, the waist of which should be a little closer to the tsuba than the kashira, and whilst it can be narrower at the top than the bottom the difference should not be great.
A good ito wrap makes a world of difference to the general feel of quality of a sword. It shoud be as flat as possible at the 'twists', very tight and very regular. It's an art form in and of itself and I'd well recommend reading up on it - it's one of those touches that can make a world of difference. I actually prefer cotton ito to either leather or silk both aesthetically and practically.
Menuki should not be so large that they can affect the grip on the tsuka and should be placed so that they will fall under the fingers rather than the palm {as yours are :tup:}. I would say that the ones you have are a bit big in that they span too much of the width of the tsuka. They're nice tho'.
Coloured same is a difficult one to speak on as it can be so much a matter of personal taste. I'm something of a traditionalist and much prefer white to anything else. The 'pimple' size should vary enough so as not to look industrially uniform. When achieving this, using the real thing is much, much better than plastic or any other synthetic alternative- of course, it's also much, much more expensive

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Anyhow, burbled too long as usual; my apologies. I hope at least a little of that was useful anyway.
Please bear in mind that I am a sword
user rather than
maker (and a bit of a traditionalist snob too

) so take my comments with as big a pinch of salt as required to make them palatable

.