Congratulations on your retirement!
Are you looking to buy off the shelf or do you want something made to order?
If you want off the shelf:
- Mesa Mark or Recto - Couldn't go wrong with either of these. They are different beasts so you'd have to play them to find out which one you bond with better
- Soldano SLO - not 100%, but a SLO could be comparative to a boutique 5150
- Freidman BE100 - Modified Marshall type amp. They sound great and very few are displeased with them
- Maybe something from Diezel? - Great German made amps, but they might not be what you're looking for as they're mostly known as high gain monsters
If you want to go made to order look at:
- KSR Orthos or Ares - Kyle is a great stand-up guy & his amps are top notch. I have a Gemini which I have been loving since it came in. Covers lots of tones & has a shit ton of options. The Orthos is the stripped down version of a Gemini and Ares is a 1 channel version of the Orthos.
- Peters Formula 7 - I have a pro dual channels which is still offered and is the older version of a Formula 7. James Peters is located in Canada if that makes a difference? Cool thing about these is you get a choice of channels. So while it's straight forward controls, with being able to pick the channels you want it's somewhat one-off customized too. And James would probably make tweaks or stick in an older channel model if that's what you wanted.
- Anything from Morris - Glen mainly builds his take on several different Marshall type amps from a 15 watt class A to a high gain monster. Getting an XS-III or Sirrom is in my future. With Morris it's mainly a matter of pick your flavor.
- Anything from Splawn - I haven't personally worked with him but from what I hear Scott is probably the best dude you'll ever work with. His amps are mostly modified Marshall types and everything I've heard from them sounds excellent. The Quickrod is always a popular choice.
- Wizard - Wizard has its die hard followings and you'll probably get several recommendations for them. BUT they are extremely pricey, like past 5K pricey. You can sometimes find them on the used market at a better price and it's usually someone selling to fund another Wizard purchase. Most everyone that has played them will say nothing else can stack up to a Wizard & they're worth every penny.
I have to give a mention of Jeremy (RedPlated) of GroundZero and Shea (Monomyth) of MonoMyth amps. They're well known members here (and elsewhere) who have been modding amps for a while and have recently created they're own designs. But both currently have a waitlist so it would take a bit before they'd get through that.
Since this is a nice retirement gift to yourself I suggest leaning toward a made to order amp. In most cases you're able to talk directly with the builder/owner and they're happy to answer questions, go over everything and walk you through the build process. Not to say off the shelf is bad; it isn't, but there's just something that makes it feel more special when you get to talk to the builder and order directly from them. Plus support to the small shop builders.