You may add to your list film hanging clips. You could also use spring loaded clips that you can weigh down further.

You have fixer, I presume. Some hypo-clearing agent will shorten wash times, and some wetting agent will help prevent drying streaks.

For measuring, I use a 1 liter kitchen jug with 50 ml interval markings for the water, and a 45 ml graduate for the concentrate. You could as easily use a syringe for the concentrate. HC-110 at dilution H (twice B) is what I normally use. I use it as single-shot developer, but you may also go with multiple uses of lower dilutions. In that case, the typical 500 ml or 1 liter coke bottle makes a good enough storage bottle.

It is easier to heat developer up than cooling it down. For the latter I use ice packs that I immerse in the developer until the temperature is correct. You could also use those plastic "ice cubes" that one gets for children's cooldrinks. It is essentially a plastic capsule containing water, which one re-freezes after use. Of course, once the developer is mixed, you cannot add ice directly as it will dilute the developer.

Hope this helps.