Re: Sorry, but ...
I think the memory of your "favorite" Dr Who is colored in no small amount by the ensemble cast chemistry, the situations (as opposed to scripts) that they find themselves mired in and the general tone of the show.
I loved most of the early doctors *when I first saw them* but they don't often wear well when viewed today (for me). I found Ian Chesterton to be violent to the point of sociopathy - and him a teacher too! - when some of the first shows were recently rebroadcast. I had remembered him much more fondly.
Troughton was fun for the most part, though I found his obsession with the recorder to be "too much".
Pertwee had the advantage (for me) of being an actor I loved in other roles - The Navy Lark springs to mind - but was saddled with the at the time infuriating lack of a working time machine and a surfeit of what I call "70s Stupids" - special effects and script "bits" that were supposed to be cool but were cringe-inducing in their naffness. Venusian Karate was one I hated, as was the Whomobile. Just awful.
Baker was, of course, almost born for the role and his concept of a time-travelling Harpo Marx was inspired. But this was also the era when more and more of the situations were huge story arcs that were wound up with technoblither on the last page of the script a-la Star Trek.
Davidson's doctor cured me of the show, mostly because I hated his companions, his tooth-achingly bad obsession with cricket and that damned celery stalk. The scripts were all gothic doom and gloom too (with the occasional brilliant one like Castrovalva).
McCoy's Doctor was a breath of fresh air, but again, the situations were dull and the companions were intolerable to me. By then I wasn't watching the show much, not making time for it, but I caught a few episodes.
I only saw one episode of Colin Baker's Doctor. I thought it showed promise in a completely over-the-top way, but as I say, by then I wasn't really paying attention and wasn't crushed when the show was dropped.
Besides, the Baker episodes were in constant rotation on PBS here in NY every Saturday afternoon. I was astounded at the show's popularity and the fans' efforts to keep it on screens all around the country. Tom Baker did a fund-raiser "bit" when our local PBS station was having a beggathon, in which he berated those who watched without subscribing at length and with great creativity. It was hysterical right up to the time they cut to someone else, anyone else for God's sake.
Paul McGann was excellent in the challenging role of trying to make Dr Who a prime time US TV product. A difficult act to bring off and pretty thankless, many daft UK viewers seeing his role as some sort of betrayal. His was the doctor that first showed us a Steampunky Tardis.
Eccleston was nothing short of brilliant. I don't kid myself that he was the only actor capable of giving the franchise a new lease of life, but he bit off huge chunks of it and made it his from the first few seconds of the opening. He also had some of the finest scripts I think have been attempted for the show. His is the doctor I wish we could have seen more of.
Tennant was fun, but began to get too shouty. He was also saddled with Donna which was the point at which I stopped watching again for a season or so. Did love Broody Tennant Doctor though.
Never really cottoned to Smith in the role. The show had some very clever plots and he was particularly clever in what he did with the role in places, but I found much of his reign to be "meh". I'm re-viewing his first season on disc so maybe I'll learn to like him better. Also: not fond of the River Song plot thingy.
And so to Capaldi's doctor. A bit of a puzzler this one for me. Half the time I love his characterization, half the time I hate it with a vengeance. A bit too much "today" in the set dressing I think. Some of the scripts have been stinkers, but some have had moments of inspired brilliance - the long way round springs to mind, as does the breaking of the fourth wall to ask "who wrote Beethoven's Fifth?". But the last season was saddled with too many problems for me. I wish they could have spread the encounters with old enemies over the four Capaldi seasons instead of mashing them into one horrendous crescendo.
Still iconic though, no matter who plays him. Especially if it's John Hurt.