Its a broad field. Friendly and optimistic could conflict with legibility, if the design got too “friendly and optimistic”.

Depending on the distance, the mood, and just how legible you need to be, you could look at some of these:

Basalt, Capitolium, Grand Central, Gotham, Whitney, Mantinia, Sophia, Metron, Parisine and the meticulous Clearview.

Some of these are obviously not for use where legibility is _critical_, and some are quite pricey, too pricey for a student project (unless you only need to spec the type, not set it.)

A good local choice would be Keith Tam’s Arrival — http://www.keithtam.net/ — not only are you using a locally produced font, but you might be able to convince Keith to critique your use of it too.

Here’s a crazy idea:
http://www.fontbureau.com/fonts/Amira
Although the x-height is a bit small for signage.

hhp

Thank you for your reply. I have carefully read through your responses.

I did consider Arrival, but Keith Tam is actually teaching in my school. I thought it would be too easy to just pick it randomly out of the hat, since that’s the only type that i know designed for signages (cough* cough* due to Keith’s heavy advertising in his type class, hehe)

I like to explore other options so i have a few to compare from.

For this project, the phrase “Big City, Here We Come” will be set in large sizes on the side of the street for driver to read as they drive, so i guess in a way it functions like a highway signage.

This tag line that i am using is to promote an friendly and optimistic feeling it’s ideal that the typeface doesn’t feel too cold.

What about Vialog?

Comic Sans meets your requirements.
I’m serious.
If you are doing a research project you should forget your prejudices, and experiment till you discover what works best.

Yes, ignore everything except your inner child…

hhp

What kind of project is it for?

There are types designed for extreme circumstances (like
Clearview for highway signage) and then there are typefaces that
are designed for wayfinding and signage (Frutiger, Whitney) and
then there are faces that just hold up well at large sizes (The Sans).

Wei, I was going to recommend Arrival as well, since I do believe you are in Keith’s class, right? He may be happy to let you use it.

Take a look at Metron, available at Storm. I have a weakness for this one.

I might have a few specimens lying around if you’d like to take a closer look.
PS

Gerard Unger’s Capitolium was designed for wayfinding to be created for the Jubilee in Rome.