I've had a number of soldering irons over the decades and some of them have been the bare-bones kind. I have needed to make the most of whatever was available.

The cheap small soldering "pencil" irons like they had at Radio Shack were insidiously bad because of the crummy solder that came in the package, and their crummy store brand solder.

I would use only Multicore or Kester solder. Much bigger difference than automatic temperature control.

These are small irons but they still get hotter than the ideal temperature that most long-term assemblers prefer to work at. At least the iron does, but maybe not the tip, especially if it's not screwed in really tight, or if a lot of oxidation has built up in the iron threaded socket the tip screws into. I used to grab the tip at the base with the curved jaws of a wire stripper and screw it in real tight whether hot or cold. Starting when new so no corrosion has a chance to build up.

Different tips will end up with different tip temperatures, but when you've got one of these going properly you can be just as effective as with a controlled unit.

The tips are copper with chrome plating which can be a thin layer, but when it oxidizes it gets more of a sheen rather than building up a crust like plain copper. Solder won't want to stick to the chrome too easy, and once it gets oxidized it's even worse. And the oxidized metal will not transfer heat properly to the work.

For splicing new pure copper wires using a temp-controlled iron, it is common to heat the copper joint with the tip until the solder melts and behaves like mercury as it soaks well into the joint. This often fails with antique wires since the old conductor has an oxidation layer on the strands so the solder will not wet them. Things like this are best carefully tinned individually before joining, using additional cleaning and flux if necessary.

Tinning the new tip is the first thing. Lots of users will wait until the iron heats up too much and try to apply a bit of solder after there is already a thin oxidation layer on the chrome tip. I like to get some solder on the point to wet the chrome as soon as it gets hot enough the first time, then unplug the iron and suspend the tip downward with a fraction of a gram of solder obscuring the point as it hardens. It will really dig into that substrate as it solidifies, and in operation the very tip is the part you are going to have to keep constantly wet with fresh solder, and basically use some liquid metal hanging there to transfer heat more effectively to the work than you can from contact with a non-wet tip of the same temperature. The shaft of the tip will become more and more oxidized, and if the point gets like that you might as well sand it down, most likely down to the copper.

Copper tins real easy but it dissolves in the solder much faster than the chrome so the tip will be much more sacrificial as you continue rinsing it with fresh solder when needed so only the freshest non-oxidized solder will come in contact with your work. With new tips or not, properly sized to the work, stuffing a PCB should not require more flux than there is in the core of the solder.

Unplug it when you're not actually using it, they do not really take that long to heat up when you need it again. They just sit there oxidizing otherwise.

Whatever your approach, you need to be comfortable with handling hot liquid metal to some extent.