At the Hilton Cologne I usually get a junior suite or a king deluxe with a view (a 4-5 category upgrade, their deluxe rooms are huge rooms with a view and a large couch, more like a junior suite despite the name) and drink vouchers and I love their breakfast. At the Hilton Dusseldorf I have received a junior suite quiet a few times as well, their executive lounge replacement has also been very decent, for me good enough to choose Hilton above other alternatives hotels.

But I passed the stage of paying premium price for a hotel just because it has a Hilton sign above the entrance door and receive nothing for my loyalty except a free bottle of water (free in many 3* hotels), a free breakfast (many very decent non-chain hotels give this for free when you book direct on their website) and an upgrade that's not a real upgrade (or a room that costs 5€ per night more...).
Especially last year when our Diamond status was extended anyway, I tried many non-Hilton hotels, I was often pleasantly surprised! I pay all my travel out of my own pocket and lately, it's my wallet that decides...

I would always pick a Hilton group hotel if I feel my Diamond benefits are worth it and my loyalty is rewarded, if not, I go elsewhere...