There are several ways to translate "suburb" in a more neutral way than banlieue.

In addition to périphérie already suggested by Jylo's comment, here are two other that come to mind:

• autour de
• dans les environs de

e.g.:

Je cherche à louer une maison dans les environs de Lyon.

There are several ways to translate "suburb" in a more neutral way than banlieue.

In addition to périphérie already suggested by Jylo's comment, here are two other that come to mind, despite being euphemisms which you rule out in your question:

• autour de
• dans les environs de

e.g.:

Je cherche à louer une maison dans les environs de Lyon.