Just had time to sit and look at your pictures properly. It is very hard to give specific advice from photos but my comments for now would be...
1. I love love love larches and would be very happy if that was my tree. Plenty to work with and no awful problems that will be difficult to remedy.
2. Some of the wire looks tight and, if it was put on at the start of the growing season, the branches will all be thickening and it will cut in if left too long. I would carefully take it all off, snip it with wire cutters if unwinding is going to risk damage or broken branches.
3. Carefully prune back the long new growth to a suitable bud then you will be able to really see what you have got and in the autumn once the needles have dropped you will be able to re-wire it where needed. 'A suitable bud' is hard to define but first cut back any growth that points straight up or down. Then, if you look at the new growth, you will see tiny brownish bumps in some of the leaf joints. Cut back so that there are just 2 or 3 left. These will grow new branches and start the process of ramification, developing finer branching. Look at the direction the bud is pointing and decide if that is where you want a new branch to grow. I then go along under each branch pulling off any leaves that are pointing downwards. Just pull them off with your thumb and finger. It does no harm and makes the branch layers look cleaner and more defined. Take the whole process slowly and really get to know your tree.
4. Then sit back, admire your new tree, take some more pictures and show us how it looks.
Have fun
