I don't sweat population growth too much, as long as technology keeps improving. There's still a lot of uninhabited land around the world - and it's not just land - we haven't even really begun to tap the agricultural possibilities of the oceans.
The only obstacle I see is an economy that devotes too much of its brain power and raw materials to luxury goods and services for a tiny minority... that devotes too much of its brain power and raw materials into marketing things people don't really want, until they feel like they have to get them - then it's on to the "next big thing".
There's a lot of junk out there because the poor don't have the money to spend, so people who do have jobs have to market to the rich (or at least the relatively rich).