pfSense

Original (from parse.y):

    'all', 'allow-opts', 'altq', 'anchor', 'antispoof', 'any', 'bandwidth', 'binat', 'binat-anchor', 'bitmask',
    'block', 'block-policy', 'buckets', 'cbq', 'code', 'codelq', 'crop', 'debug', 'divert-reply', 'divert-to',
    'dnpipe', 'dnqueue', 'drop', 'drop-ovl', 'dup-to', 'ether', 'fail-policy', 'fairq', 'fastroute', 'file',
    'fingerprints', 'flags', 'floating', 'flush', 'for', 'fragment', 'from', 'global', 'group', 'hfsc', 'hogs',
    'hostid', 'icmp-type', 'icmp6-type', 'if-bound', 'in', 'include', 'inet', 'inet6', 'interval', 'keep',
    'keepcounters', 'l3', 'label', 'limit', 'linkshare', 'load', 'log', 'loginterface', 'map-e-portset', 'match',
    'max', 'max-mss', 'max-src-conn', 'max-src-conn-rate', 'max-src-nodes', 'max-src-states', 'min-ttl', 'modulate',
    'nat', 'nat-anchor', 'no', 'no-df', 'no-route', 'no-sync', 'on', 'optimization', 'os', 'out', 'overload',
    'pass', 'port', 'prio', 'priority', 'priq', 'probability', 'proto', 'qlimit', 'queue', 'quick', 'random',
    'random-id', 'rdr', 'rdr-anchor', 'realtime', 'reassemble', 'reply-to', 'require-order', 'return', 'return-icmp',
    'return-icmp6', 'return-rst', 'ridentifier', 'round-robin', 'route', 'route-to', 'rtable', 'rule',
    'ruleset-optimization', 'scrub', 'set', 'set-tos', 'skip', 'sloppy', 'source-hash', 'source-track', 'state',
    'state-defaults', 'state-policy', 'static-port', 'sticky-address', 'syncookies', 'synproxy', 'table', 'tag',
    'tagged', 'target', 'tbrsize', 'timeout', 'to', 'tos', 'ttl', 'upperlimit', 'urpf-failed', 'user'

Original fuzzy:

    'allowopts', 'binatanchor', 'blockpolicy', 'divertreply', 'divertto', 'duptoicmptype', 'icmp6type',
    'ifboundmaxmss', 'maxsrcconn', 'maxsrcconnrate', 'maxsrcnodes', 'maxsrcstates', 'minttl', 'natanchornodf',
    'noroute', 'nosync', 'randomidrdranchor', 'replyto', 'requireorderreturnicmp', 'returnicmp6',
    'returnrstroundrobinrouteto', 'ruleset_optimization', 'settos', 'sourcehash', 'sourcetrackstatedefaults',
    'statepolicy', 'staticport', 'stickyaddress', 'urpffailed'

New (to be included from original):

    'crop', 'dnpipe', 'dnqueue', 'drop-ovl', 'ether', 'fail-policy', 'file', 'keepcounters', 'l3', 'map-e-portset',
    'match', 'ridentifier', 'syncookies'

Custom (pfSense specific):

    'arrow', 'codel', 'error', 'filename', 'fragcrop', 'fragdrop', 'IPsec', 'L2TP', 'maximummin', 'OpenVPN', 'pppoe', 'pptp'

Minor nit but it looks like if the keyword is included in two different sections (Like Original and New) the error message is sent twice.

The following input errors were detected:
    Cannot use a reserved keyword as an alias name: file
    Cannot use a reserved keyword as an alias name: file
    There may be additional errors. Fix the noted problems and try again.

Seems to prevent the aliases from being created just fine.