2.2 froyo - I keep getting storage errors but I have plenty of free space, what is safe to remove from internal storage?

I keep getting these errors:

^{Screenshot #1: install errors (click image to enlarge)}

But according to the storage settings I should have plenty of free space:

^{Screenshot #2: free space (click image to enlarge)}

I'm assuming, from reading similar questions, that it needs more space to perform the install even though I've moved every app possible to the sd card. I have cleared the browser cache and went through and cleared the cache of every other app, bringing me up to ~15MB. I used Ti to integrate 2 updates into the ROM, and that freed up enough space to update Dropbox. I installed the DiskUsage app, and this is what it looks like:

^{Screenshot #3: disk usage (click image to enlarge)}

Is there anything else that I can do about the 160+MiB of Data or 80+MiB of Applications? (I misunderstood how the app works, it looks like the data for Dialer Storage is 12.7MiB and Browser is 11.9MiB, what would I lose by deleting those?)

Update: Here's a screenshot from App2SD:

^{Screenshot #4: app2sd (click image to enlarge)}

Update #2: here are screenshots showing the Browser app and its caches cleared:

^{Screenshot #5: browser cache: cleared, #6: settings: browser cache cleared (click images to enlarge)}

Update #3: As a long term update, I think this is partially a permissions issue with apps that I've moved to the SD card. I can move an app at a time back to the phone, and the update will succeed and then I can move it back to SD. Is there some sort of recursive chmod I can run to allow it? Here's a snippet of the ddms log when updating an app:

01-29 10:50:18.420: I/PackageHelper(16890): Size of container 2 MB 400941 bytes

01-29 10:50:18.428: D/VoldCmdListener(1156): asec create smdl2tmp1 2 fat {} 10096
01-29 10:50:18.428: E/Vold(1156): ASEC file '/mnt/secure/asec/smdl2tmp1.asec' currently exists - destroy it first! (No such device or address)
01-29 10:50:18.428: W/Vold(1156): Returning OperationFailed - no handler for errno 98
01-29 10:50:18.436: E/PackageHelper(16890): Failed to create secure container smdl2tmp1
01-29 10:50:18.436: E/DefContainer(16890): Failed to create container smdl2tmp1
01-29 10:50:18.631: D/dalvikvm(1298): GC_EXPLICIT freed 15097 objects / 741152 bytes in 173ms
01-29 10:50:18.662: D/Finsky(16687): [25] 1.packageInstalled: Package install status for "null" is -18
01-29 10:50:18.694: D/Finsky(16687): [1] InstallerTask.cancelCleanup: Cancel running installation of jackpal.androidterm

Update #4: After going through a somewhat tedious process of partitioning the SD for Link2SD, then moving items to phone, and linking them to the new SD partition, the Google Play store was finally able to update the apps. I'm still really low on space though, I'll have to try clearing the browser data and the MMS messages again.