Shaky camera doesn't show it at its best but for size reference: U5=SOT23-6 C13, C15=0805 R32=0603 all with 0.7mm characters. These markings are 0.7mm/0.15mm pcb manufactured by Elecrow low-cost service who's rules are 0.8mm/0.15mm so it's not a surprise the eye of 'R' is filled. Not sure how useful this image is now, but I've taken it already and will upload it.

Obviously user instructions and pinouts as large as you can make them within reason. Say 1.8mm between centres would suggest something of the order of 1.4mm could work for you. In the filter window just leave 'Object Kind. Alternatively, instead of right-clicking a designator, you could also right-click a component instead and select 'Find Similar Objects'. If you are trying to choose a house style for your own work, consider what pitch you will be laying your 0805s out and choose something which works. Once in the inspector, simply uncheck the 'Hide' box under the 'Graphical' heading and press your enter key: This will apply the change to all of your designators. Anything less than 1.2mm and I print out a zoomed copy to use as a reference on the bench so making the effort to put the designators in sensible positions is rewarded in the print out even if the silk screen is nearly illegible. Where I can, I use 1.2mm for legibility without magnification, but will go smaller/larger depending on layout constraints.

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