The decimeter is certainly an overlooked unit, and it’s a shame it’s relegated to relative obscurity - I use it occasionally even if people give me weird looks. Ideally I think something in the range of 20-30cm would make for a nice base unit - about the length of a forearm. Deci-units around the length of a finger segment, and centi-units being a slightly larger millimetre-equivalent. A deca-unit would be about the height of a doorframe.

Don’t misunderstand me, imperial sucks. I just wish the metric system had defined the metre to be smaller, that’s all.

See my other comments in this thread. I think most people would prefer if the common measurements they made with common units landed in the number range of about 0.2-10-ish. The human brain is good at visually estimating small groups so any unit system should try to lean into that and put the scale of commonly measured values in that range. Obviously as things get bigger you end up with tens or hundreds of units which start to lose semantic meaning, especially for quick estimations or relative comparisons, so you should start thinking of switching units at this point. Likewise when values get below about 0.1 they get hard to visualise, so most people switch units here.

My point being - I think the base unit of one metre is too large for most daily tasks - most things that are around a human scale end up being less than one metre, and I think the centimetre is too small - most things on the human scale end up being dozens of centimetres at least. Both fall outside that ideal range of ‘a small handful’ which the brain is good intuitively and subconsciously working with.

You’re right, I have no interest in sports. Though in that case under this modified metric a decametre would be approximately on the same scale as the previous metre.

Don’t get me wrong, imperial sucks, but the scale of the typical measurements with typical units lands nicely in what the human brain is good at visualising - small groups of up to about 10 (see my comments to other people in this thread). I think most people would prefer when the common measurements they make with common units end up in the range of 0.2 to 10-ish. Centimetres are too small for that and you measure using dozens or hundreds of them, which starts to lose semantic meaning, which makes visual estimation a bit trickier, especially with comparative distances. You start thinking in terms of tens or hundreds of cm visually to keep it under control which is just another layer of cognitive load. I think the perfect unit system would avoid this as much as practical. The existing metric metre is fine for outdoor activities, but I would argue most people aren’t out measuring fields all day, they’re looking at things on the same scale as their own body for the most part. Metres are a bit big for that.

The metric prefix system is a fantastic invention, akin to the arabic number system. Honestly it’s surprising no one came up with it sooner… but (and I’m sure I’ll catch some flak for this) the metre is an awkward length - it’s too big for human scale measurements. The decimetre is not as bad but still not very good, and it’s also not commonly used. The centimetre has the opposite problem - it’s too small for the human scale but too big for precision work.

Don’t get me wrong, the horrible conversions between imperial units make the system unusable for me, but the unit lengths themselves are scaled to humans because they weren’t initially defined arbitrarily by some committee (why should the distance from the pole to the equator be used as the baseline for a measurement used by humans?). I think the inch and foot are great lengths to use on a daily basis, they feel quite natural.

What annoys me the most is that we could have had the best of both, since the foot and inch are only a factor of 12 apart, so we could have had a metre measuring about one foot and a decimetre measuring about an inch.