Splinterlands Advice Please?

I currently have a deck that allows me to reach Silver III each and every season, I don't really want to advance up to the next levels until the new Chaos Packs become playable. I have just over 15000 Power (40,000 Power with 25000 of it rented out.) as well as 140,000 in DEC.

The advice I am looking for is based on the fact that each or every other day, I invest some of my earnings, winnings into new cards, I am just wondering what peoples thoughts are for buying GOLD cards, rather than buying cards to rent out, and do you think I would profit better this way.
Please comment below, would especially like to hear what @splintertalk thinks or anyone else with similar strategies.

Thanks in Advance