When it comes to callsigns, I have traditionally always felt like Maxwell Smart... "Missed it by THAT much!"
Novice call: WD5CCV... WB5? BTC? CTZ? and so on, ad nauseum
My first repeater (years later): The repeater had a diode matrix (put diodes in to spell out the dits and dahs), so I went for a shorter call: KI5DM... Great... when I was a Novice, we were all jealous of old timers with calls beginning with the the letter 'K'... they weren't assigned anymore. So I was happy to have a 'K' call. Then a ham licensed much after me says, "Wow! You had a 'W' call and you gave it up?!!!" (This was before vanity calls and all that was being assigned were Ks... what goes around.) Anyway, I kept getting mistaken for another ham in the area with a very similar call. Oh, well... moving on.
Upgrade to Extra and moved: AB5HB... was fine with that until we planned to move again and I was going to get back on HF... and CW. Too many dits!
Moved: AC5DK... was hoping to get either AC5DC (which went to an electrical engineer; issued, not vanity!) or AC5DX. (Missed it by THAT much! Either direction!) Sometimes it was so hard to get stations to get the DK and not hear DX... I even sent a card to a DX station once only to get back a card several green stamps later addressed to AC5DX. ARGH!!! (I wonder how many cards that guy got through the bureau that he wondered where it came from.)
After about 5 years off the air, we moved to a new call area: AJ4YC. YUK! I didn't want to be 'that guy with the 5 call' so I had put in for a callsign change when I put in my change of address. But that call was just terrible... voice and CW both. I think the FCC shows I had that call for all of a day or so. For the first time, I looked seriously into a vanity call.
Vanity call: N4UFO. It had been available for a month... belonged to a Silent Key. Could NOT believe it was available. I hesitated for a second, not wanting to be labeled as a card carrying member of the tin foil hat brigade, but my wife said, "Go for it! Just find me a cool callsign, too!" XYL is now N4ICY... she says not because she's cold, but if anyone wonders, she points at me and they'll reply, "Oh... I-C-Y!" (I see why)
BUT... while I love the call and it gets a lot of comments (some DX ops will remember me from band to band)
, Maxwell Smart was not far behind... unbeknownst to me at the time, W4UFO lives just 12 miles from me.
The bottom line... in my life, the different callsigns have marked different evolutions of my ham experience... it's completely personal whether you get a new one or not. Just get one that YOU are happy with... but when you find it stick with it. I have had friends that had cool calls, but spun the wheel of upgrade call re-assignment and regretted it later. But honestly, if you plan to chase DX or operate a lot of HF, getting something shorter than a 2x3 will be a big help. About the only vanity calls that I, personally, don't care for are when people get their initials... but that's my hangup, to each his own. It's just right up there with those vanity car tags where no one but the owner understands what it means...
The only real thing about changing calls is, if everybody knows you by one, may take them a while to get used to the new one... it IS like changing your name. That's why I only did it when moving or when i'd been off the air for a while.