The center bore of the aluminum reed block has circumferential grooves machined into it where it contacts the crankshaft. These grooves serve as a "labyrinth seal" to isolate the fuel air charge of #1 cyl from #2 cyl, and vice-versa.
If these grooves are worn, the motor will be hard to start and idle poorly. But a lot of other things can cause that, too. I have never seen worn reed block on a small Twin, but it does happen quite often on the larger Inline Fours and Sixes.
If you do take your reed block off the crankshaft, it splits into 2 halves. Inspect the grooves, they should be sharp and well defined. If the aluminum is worn or mushroomed, the reed block must be replaced.
Bad crankshaft seals will make a motor really cranky. If your seals were really loose on the crankshaft, that's likely part of the problem.\
Unless a reed is "sprung" such that it won't come off the reed block, stuck way open, or cracked, it's OK. Ever-so-slightly sprung off the reed block won't hurt a thing.
By now I expect you've pulled the rotating assembly out of the block, how do the pistons, rings, & cylinder bores look? If the pistons are all chewed-up, it won't run well, either. A new set of rings and a quick deglaze with a ball hone (if you can find one that small) should make it run like new.
HTH, let us know what you find.........ed
