One set for all types of play: I’d go with Legend’s King’s Indian plastic set.
One Wood set: Jaques 1853 Club set… the real deal, not a repro.
The one board would be the JLP Folding board from Rafael.
The clock would be the DGT3000.
One set for all would be the Ultimates in appliance white.
One wood set would be a real antique 1853 to 1870 9 cm Jaques set with what looks like a Paulsen knight. An alternative might be a vintage Chavet B210.
One board would be a vintage Drueke from the 50s-60s.
One clock would be the only one I have ever touched... my DGT3000.
Robust pieces, playable, beautiful… with an indestructible board. Holger’s Philippines pieces and my refurbished (local find) solid wood board. I am a little embarrassed posting this where others are posting more magnificent wooden sets but alas …. If my wife asked me to keep only one set - this is it. As yet, I don’t own a plastic set but wish I owned one of Shelby’s buttered pieces … alas, freight stopped me purchasing that set when they were available. 
Tough one! I'd say this undestructible set

But I go for this set with unknown board and Garde clock (not the one on the pic).

Do you have some images or links for the Jaques 1853 Club set?
For me, the plastic set would be the Legend Alegria.
The wood set would be the HoS Craftsman in tulip wood and magnolia wood.
The board would be the JLP 21" folding (with ACE's custom red/black mousepad hiding underneath
.
The clock would be any that would warn me when I'm about to blunder!
Just wondering, how do you stash your 250+ sets? ![]()
Only one set? The Bobby Fischer Ultimate set (v3), which is a recent purchase.
Love it! Sturdy, feels great, great stability… ticks all the boxes. In case accidents happen and either the set or pieces are lost, fairly easily replaceable at a very reasonable price.
I also have a 3.9” Craftsman Series set from RCM which have some beautifully carved Knights! But if I had to let a set go, it would probably be that one and keeping the Ultimate.
@bananamoon how many ELOs does the cognac help your game? FYI, I love reassess your chess.
@madmacsback the JLP has been on my wishlist for a long time. Last year I accidentally ordered the non-folding version and went on the wait list. Now I'm in Europe and the duties are very high.
@theonecalledmichael I love the board with the small border.
My goto board is usually a vinyl board with weighted plastic pieces in a nylon carry case from Chesshouse. One of my rooks has a broken turret and time to replace. Board is well used so it could probably use an upgrade to a silicon or mousepad board. Ohhhh I miss traveling and playing OTB. Here I am getting schooled by a fellow chess.com player (yes... the 10yr old kid!) on my travel board. Actually I see the board on the left is mine... don't know how/why I got bumped (I think no one wanted to play the "kid") 
Really hard to give up ANY of my Noj pieces though. Noj GM Pavasovic pieces might be my favourite (it's not usually discussed). I have two other BCE sets and another on the way. Still love my Tal and Dubrovnik.
I have an EraRetro Tal set on the way as well, but I don't think I have a board large enough for it.
I have a semi-travel board like this one. But I like the minimalist design with no boarder.

So... circumstances of why I can only have one set need to be considered. If it were the zombie apocalypse I'd have to go with my plastic pieces, vinyl board and nylon carry case so I could make a run for it at a moment's notice (broken rook and all).
Tough one! I'd say this undestructible set
like that one. what set it is?
If I had to choose one set, it would be a durable fun everyday set. Ultimate Butters with a Red&Black mousepad board.

Tough one! I'd say this undestructible set
like that one. what set it is?
That's size 6 Chavet. The same set but size 5 was used for the WCC 2000 match between Kramnik vs Kasparov.
For plastic, I would have to say the Butters, I really like that set.
For wood, I would keep my very first set, a no name wooden set that my lovely bride of 36 years bought the 2nd year we were married. It is unweighted and for years it sat on an undersized board (a Drueke, I think) but I keep it stored away now to preserve it. I do not think she knows I still have it.
did some research on that Chavet set, but it seems that the new design brings some flaws, like loose weights.
I'm looking for some solid nice wood set like that. can you guys send me on the right direction?
thanks, in advance.
did some research on that Chavet set, but it seems that the new design brings some flaws, like loose weights.
I'm looking for some solid nice wood set like that. can you guys send me on the right direction?
thanks, in advance.
I'd suggest that you start a new thread for your question. You're more likely to get relevant answers.
If you were forced to only one one Chess set, which set would you have?
If I wanted one set to use for all types of play, it would be a plastic set, The Ultimate, latest version would be the one.
The one wood set I would have would be the Noj Dubrovnik Minceta.
The board would be the FlexPad board from The Chess House. And the clock would be the V-Tek in black.