They are some of my favourite Pokemon, I no longer pick a singular favourite because it's not fair to the others, and all the Pokemon I like are equally wonderful. You can check the About Me section to see a short list. Hmm, not sure if I really relate to them as in they would be a signature, singular Pokemon to represent me. Picking one of those would be extremely tough, unless there is the perfect Pokemon for me out there. This warrants a thread!
Latias is extremely cute, in both Pokemon and Human form, and the ability to transform and become invisible is amazing. As well as telepathy, it's extremely intelligent and can understand the emotions of people, as well as fly like a jet. That's so cool! Latias is awesome. I'm a Sapphire player so it's the design and capabilities of the pokemon that draw me to it.
Pikachu is just so iconic, as well as all those adorable moments in the anime make him cute and desirable to represent. I think his design is perfect for the franchise, yellow is my favourite colour, so a cool little yellow electric mouse is definitely for me! :) Those are weak explanations, but yes I'll google Haruhi when I have a few days to burn :)