Wildcards will not be expanded in
$PATH, no. Per the bash manual, PATH is:
A colon-separated list of directories in which the shell looks for commands
Coming from another direction, the Command Search and Execution section of the manual says, in part:
If the name is neither a shell function nor a builtin, and contains no slashes, Bash searches each element of $PATH for a directory containing an executable file by that name.
... (my emphasis) -- which makes no mention of any special processing done on the path elements, only that they are expected to be directories (as-is).
I'm not sure off-hand what the limit is for the size of a bash variable; I suspect it's available memory. PATH doesn't need to be exported, but many people do; if it is exported, it will need to fit along with other environment variables and arguments into
getconf ARG_MAX (ref: https://unix.stackexchange.com/a/124422/117549). A large PATH directory should not induce too much of a performance overhead, since bash uses a hash table to remember locations of previously-found commands (per-session).
If you do hit a limit (visual or technical) with adding each individual application directory to your PATH, I would recommend adding one "symlink" directory to your PATH where you then link in the desired executables from the various applications.