Non-malevolent synonym of envy
What's a word meaning
"I want something very similar to what you have, but I don't feel resentment for your possession of it, nor do I wish for you to lose it"?
Greed doesn't seem targeted
Envy means wanting to take what someone else has, and feeling satisfaction upon seeing them lose it
Jealousy is a defensive fear of loss
Lust seems targeted at the person themselves
How about desire?
Desire noun a strong feeling of wanting to have something or wishing for something to happen.
The noun covetousness has the idea of wanting what someone else has (not just something similar to it), without malevolent intent.
Covet verb Yearn to possess (something, especially something belonging to another) - ODO
The words yearning, desire, etc convey the idea of wanting something, but don't necessarily carry the idea that someone else has one.
A noun that comes close to both senses of wanting something and referencing something external is aspiration:
Aspire verb Direct one’s hopes or ambitions towards achieving something - ODO
Unfortunately, it tends to be applicable only to greater degrees of intangible qualities. For example:
i aspire to reach his level of coolness - crybaby
emulate -- From Merriam Webster
to try to be like (someone or something you admire)
to strive to equal or excel
In the case you describe, you would want to emulate the qualities that made the person successful and thus able to have the life that you admire and wish for yourself. If you succeed, you take nothing away from the person you emulate.
Keeping up with the Joneses
"Keeping up with the Joneses" is an idiom in many parts of the English-speaking world referring to the comparison to one's neighbor as a benchmark for social class or the accumulation of material goods. To fail to "keep up with the Joneses" is perceived as demonstrating socio-economic or cultural inferiority.
google.com
There is nothing malevolent here. To some it's not even negative. Though it does go against some less materialistic philosophies.