Carlos Silva

the insulated wire is almost certainly why your resonant point is off — insulated wire has a velocity factor less than 1 so it behaves electrically longer than its physical length. rule of thumb is you usually need to trim a few inches per leg compared to bare wire, sometimes more depending on the insulation thickness. i wouldnt be surprised if you need to take 3-4 inches off each side to pull resonance up toward the middle of the band.
on the balun question, for a basic dipole fed with coax i usually just go with a few turns of coax wound into a choke right at the feedpoint, works fine for most situations and costs you nothing if you have extra feedline. a good 1:1 current balun will do the same job more predictably especially if youre running higher power but honestly for casual HF operation either way is fine. the common mode current thing is real though, if you skip it entirely you might find your SWR changes when you touch the coax or your audio picks up RF. learned that the hard way on my first dipole back in the day.

so ive been at this for about three months now, just got my general and been trying to actually get on cw which was kind of the whole reason i got into ham radio in the first place. i picked up a used bencher paddle off ebay and im running it into an old MFJ keyer i borrowed from a club member.
the problem is everything i send just sounds... off. like the dits and dahs kind of run together sometimes and other times theres this weird gap in the middle of characters that shouldnt be there. ive messed with the weight and speed settings a bunch but i cant seem to find a setting that just feels right. im probably sending around 12-13 wpm which i know isnt fast but it should still sound clean right?
is this a paddle gap adjustment thing? i honestly have no idea how tight the contacts are supposed to be. the previous owner might have set it up weird. or is this more about my hand technique and i just need more practice. been using the G4FON trainer to practice receiving and im actually doing ok there, its just the sending that feels sloppy.

yeah the two sites arent exactly the same feed — DXwatch aggregates from a bunch of different cluster nodes around the world and QRZ has their own spot feed that i believe pulls from a slightly different set of nodes, or at least processes them differently. the delay you're seeing is totally normal. sometimes a spot originates from a node in europe and it takes a bit to propagate through the network to whatever server QRZ is polling. its not you doing anything wrong.
for android honestly i've been using HamSphere's cluster feature just as a backup but my main go-to for alerts is actually just setting up a filter on DXWatch and leaving it open on an old tablet. theres also an app called DX Alert that used to work pretty well, not sure if its still being maintained though. if you're serious about 17 and 12 you might also want to look at the ON4KST chat for those bands, thats where a lot of the serious guys coordinate before and during a pileup, way faster than waiting for cluster spots sometimes.

the insulated wire is almost certainly why your resonant point is off — insulated wire has a velocity factor less than 1 so it behaves electrically longer than its physical length. rule of thumb is you usually need to trim a few inches per leg compared to bare wire, sometimes more depending on the insulation thickness. i wouldnt be surprised if you need to take 3-4 inches off each side to pull resonance up toward the middle of the band.
on the balun question, for a basic dipole fed with coax i usually just go with a few turns of coax wound into a choke right at the feedpoint, works fine for most situations and costs you nothing if you have extra feedline. a good 1:1 current balun will do the same job more predictably especially if youre running higher power but honestly for casual HF operation either way is fine. the common mode current thing is real though, if you skip it entirely you might find your SWR changes when you touch the coax or your audio picks up RF. learned that the hard way on my first dipole back in the day.

yeah i had the same issue when i switched from FM to HF, took me a while to figure out that SSB audio is just a completely different animal. one thing nobody told me was to make sure youre actually on the right sideband for the band youre on. i know that sounds obvious but i was running USB on 40m once for like 20 minutes before someone politely told me. doesnt affect audio quality directly but you sound absolutely terrible to everyone else lol
the bandwidth thing you mentioned is worth playing with more though. i ended up somewhere around 2.8kHz for general ragchewing and tighten it up if the band is crowded. also make sure youre not standing too close to the mic, i was practically eating mine and it was causing all kinds of low end buildup

i just passed mine in march so pretty fresh in my memory. the math questions are the ones that tripped me up at first but most of them are the same formula over and over just with different numbers plugged in, like once you get reactance and resonance calculations down you're basically set for a chunk of them. the filter stuff i just memorized the shapes honestly, highpass lowpass bandpass whatever, not sure i could actually design one but i knew which answer to pick.
for what its worth i operate pretty similar to you and i still think it was worth doing just to say i did it, and my local club has a few people who only really talk to extra class holders which sounds elitist but they know a ton and its been good for me to be in that circle lol.

VARA HF has gotten really widespread in the last couple years, most of the HF gateways ive connected to support it fine. You dont need PACTOR unless you're going somewhere really remote or dealing with a gateway that hasnt been updated in a while. The VARA FM on VHF is solid too if you havent tried that side of it.
The hybrid network thing — yeah that confused me too when I first dug into it. Short version is a hybrid node can route messages peer to peer without hitting the internet, which matters a lot in a real disaster scenario where the CMS servers might not be reachable. Regular RMS gateways relay everything through the common message server over the internet. As a regular user you probably dont need to think about it much unless youre planning emcomm use where you genuinely cant assume internet access. Then it starts mattering which nodes are hybrid capable.
Running your own RMS relay is worth it if there's a coverage gap in your area, but if you've already got good gateway density locally it might just be redundancy. check the Winlink map and see what the actual coverage looks like around you before committing to the hardware and the ongoing maintenance headache.