Advice
I agree wholeheartedly with Fred of Xenonsoft in that a logo design is created foremost to represent a brand - the brand being what the company offers it's customers and how it consistently 'behaves' as a company.
So really the company must be decided upon first before you start designing. For instance what is it about these colours and patterns represents Signa? What do they do or how do they behave that means this is a good visual representation of their offering?
Think about this first and foremost above than simply trying to create something attractive. A logo design should really have some some of meaning and to be visually appealing to it's target market. Who are the target market of Signa, who do they sell to?
Once that is established you also need to think about practicalitiies and my recommendation would be;
1. Try to keep a logo design inside of three colours, especially if it's not an illustrative logo. Should the company decide they want to have this printed on a Tshirt, or printed in Pantone colours, that many colours is going to cost them a fortune, thus you are making it harder for them as a business to utilise the design in all ways.
If it's an illustrative logo sometimes more than three colours are required to make the illustration work, but this is not the case for a graphical logo such as this.
2. Spacing practicalities. This design is very tall, if it were printed at a very small height, for instance on a business card, or on a promotional item such as a USB Drive (print that logo at USB drive sized also), the text is going to be hard to read. The company name should be readable at all print sizes.
3. Drop shadows. Make sure the design also works without effects such as drop shadows (in this case it does I believe). If it doesn't it needs to be revised. Sometimes a logo may need to be embroidered onto a work shirt for instance and you can't embroider special effects like gradients and drop shadows.
For further advice on becoming a successful design freelancer you can visit my blog and read 'freelance graphic design guide';
Truly Ace Graphic Design Blog
Best Wishes
Amanda