You need to look at your travel and see what chain naturally fits with it. You also need to look at the cost to achieve top tier, how many unnecessary stays are done to achieve it, and what it would cost you out of pocket for the benefits you find attractive. I loved being Starwood platinum but had to make the decision that my travel no longer supported two top tiers. I chose to maintain Hyatt. Now, if I stay at Starwood I look into using extra points for a higher level room. For example, at the Augustine in Prague, a base room was 12K points. Two levels up was an additional 2.5K points. It was well worth it. The hotel was sold out so even plats weren't getting upgrades. One plat complained on FT about booking a base room and being left in it. Their base rooms face a tram line and are noisy. Breakfast at the hotel is 21 euros. We didn't eat there, but we could have had breakfast for two days for less than the cost of one unnecessary night in a hotel.
Also, consider the Hilton credit card that comes with gold status. I believe it's called Citi Hilton Hhonors Reserve. At Hilton, gold delivers many of the same benefits as diamond. We have the card and plan to keep it in perpetuity. It's worth the annual fee.
If you decide to pursue Starwood top status, then get both of the SPG AMEX cards, the personal and the business card. Each card gives 2 stay credits. That is really helpful in chipping away the number of stays you need to do in a year. If you want some status (though it is rather weak), and you have AAA, then you can get a status that is almost equivalent to gold.
Look at where you have airline status and see if it can be leveraged to give you hotel status. We are plats on United. I already have lifetime plat status on Marriott, but my husband does not. His UA status gives him Marriott gold. That's pretty good.