I agree with this. Maybe you are trying to treat this too much like a regular tree instead of a raft. I'm not sure what your end goal is, but most rafts and forests I've seen do not have very thick trunks unless they are old. Nonetheless it looks good so far- the twin trunk in the middle is nice, but as you said, careful of scars.

Comparing good 2 years of growth, with several cutbacks and repots. Not unhappy

This winter saw us have night time temperatures at -15c, with daytime not over -10 for about a week. This ulmus was in a shed, where temps are generally a few degrees higher. I doubt it ever was warmer than -10c in there though as it has open ventilation to the outside. And the result.. A few cm of bark seems to have cracked. I am curious to see how this will develop over the next years.

Somewhere I mentioned the roots. As an example the sort of roots this one has:

The cracked bark: nice natural aging .
Roots: looking good , but i suppose you want more roots underneath the raft?

exactly. Which is why I trimmed the "old" main rootball quite extensively, so the new singlar roots on the raft & the scars next it are encouraged to develop

Just a little update. It was thinned a lot, earlier this month as too many new branches popped, an updated picture:

I like it!!
In general: starting to like Chinese elms more and more, the little leaves are great for the general appearance/ratio trunk-leaves of a bonsai.

lucR wrote: I like it!!
In general: starting to like Chinese elms more and more, the little leaves are great for the general appearance/ratio trunk-leaves of a bonsai.

Add to that their lust to grow, and no real problems with pot culture.. I love the species, and feel everyone should have one or more elms. Great starter trees too. It is just sad that mass production makes this an ignored species.

The leaves on this are now only a few mm. They will become larger of course as the branch extends. But imagin this 2-3 times as tall and as wide as the pot, with 2mm leaves...

I've never had an Elm, I think it is going to be my next purchase.