It's a bland but sturdy logo. Adding the little embellishments is making it messier and then tacking on of 'design' is awkward. None of the accoutrements integrate well and they'll all suffer when reproduced at different sizes.

I'd suggest moving away from the original TTF in your experimenting. You can always come back to it, but spend some time rethinking it entirely.

> Original logo - a tad bit boring

Not only boring but also inappropriate for the company's product; it could be a logo for a company that makes machine parts.

> it’s a registered trade mark, so
> unfortunately it cannot receive major modification

Well it's not like they're legally required to use the same logo forever; most companies revise their logos periodically, sometimes in very major ways.

But anyway, most of those variations you show will not reproduce well in smaller sizes, especially the tiny diamond. Try making prints of those logos postage-stamp size and see how they hold up.

If the client just wants tweaks, you might consider leaving the letter shapes alone but maybe reverse them out of a shape (an oval or jewel shape or whatever) and then soften the overall look through the use of color.

Thank you for your kind reply guys.

These feedback really helped. As JamesM suggest the original TTF logo is indeed very inappropriate for a jewellery company, it's very unfortunately that I am current stuck with it.

I've made further changes to the logo in order to counter the sharp and heavy font

I think that new approach has possibilities, but a few suggestions. The word "Design" is very tiny in most of them and won't hold up well in small sizes. I would probably put "Design" outside of the shape (as you did in one of them) and make it larger.

Consider putting Design in a more feminine font (perhaps a nice script) as that would be a way to counterbalance the corporate look of TTF and soften the overall look.

You also might want to consider using softer colors, more like pastels.

As for the specific shape, I dunno, that's just going to take a lot of thought and experimentation. A shape with curves will help soften the logo, although a hard-edged jewel shape certainly might be appropriate too.

As research you might want to search "jewelry logo" (or similar phrases) on Google Images to see example logos of other jewelry companies.

I like the diamond shape (blue). wonder if you played with the shape a little more so it looked more diamond'ish. diamonds come in all shapes/sizes. =)