I like the creature idea. Here's waht the Basic Rules say about modifying the Hydra, we could probably echo something similar for 'bots ---

MOVEMENT:     []   2   []   3   []   4   []   5   []   6   []   7

SPECIAL ABILITIES: (Roll 1d10 three times; roll again if an ability repeats)

__Ability____________________________Effect________
[] 1 Smashes Through Walls --- Walls don t effect movement; moving through a wall creates rubble where characters must stop before crossing.
[] 2 Shakes Ground --- Characters can move no faster than half their running speed.
[] 3 Teleport --- Creature can teleport up to eight spaces away once every three turns.
[] 4 Spins Web --- Creature can permanently block the square it is in by spending one turn standing still and spinning a web. Also can throw a web and catch a character for two turns (treat as a grenade for range and hits).
[] 5 Doze Gas --- Same as doze grenade but always misses target square.
[] 6 Grows Stronger --- Gains 10 Stamina points if hit by a weapon it is immune to; if hydra has no immunity it gains 20 points by damaging a monorail station*.
[] 7 Grows New Attack --- Gains one attack when hit by a weapon it is immune to; if creature has no immunity it gains one attack when hit by a skimmer.
[] 8 Takes Extra Damage --- Takes 2 extra points of damage when hit by a weapon other than one the creature is immune to (choose which weapon at start); if hydra has no immunity it takes 10 points of damage from each skimmer accident.
[] 9 Loses 1 Attack --- Loses one attack if a single shot causes 15 or more points of damage.
[] 10 Changes 1 Ability --- On its next turn after being hit by a weapon it is immune to, the creature can change its attack its defense or one special ability (by rolling dice); if it has no immunity this happens when it damages a monorail terminal.

* To damage a monorail terminal the creature must move into the terminal's space and stop. On the next turn the player controlling the creature rolls 1d10; on a roil of 1, 2, or 3 the creature has bitten through the terminal's power cables and shut down the terminal. The creature can move and fight normally on the next turn. No monorail cars can travel across that terminal for the rest of the game. If players ride the monorail to that terminal, they must get off there.
 
 
 

GOALS: (Select one of the following)

 [] Eat enough to lay eggs. The PGC players must pick 15 pieces to represent civilians in the downtown area. He places each piece in a different building on the map. When the alien creature moves into the same space as a civilian piece the player rolls 1d10: on a roll of 1-5 the creature eats the civilian. The PGC player can move civilian pieces only if they are being attacked by a creature or are next to a PGC character. Civilians may not move off the board. PGC characters may not be eaten. The creature wins if it eats eight civilians.

[] Find someone. The PGC player chooses five counters and secretly marks one. He then mixes up the pieces and without looking places each face down in a different building that covers 16 spaces or more. The creature must search the buildings for the marked piece. Once in the building the hydra player must roll 1 2 or 3 on 1d10 to find the face down counter and reveal its identity. if the creature finds a dummy counter it discards it.

[] Build a nest. The creature selects a building that covers 16 or more spaces and writes its name on a piece of paper. The creature must wreck three buildings from a different complex and carry the rubble back to build its nest. To destroy a building it must move next to the building and roll a 1 2 or 3 on 1d10. The creature also must cause one accident and carry a destroyed skimmer back to its nest. The creature can carry only one load at a time. When carrying material back to its nest the hydra moves at half speed. The creature wins if it finishes its nest.

[] Destroy the town. The creature must destroy 40 or more points of buildings to win the game. The sizes of buildings. their point values and the numbers that must be rolled on 1d10 to destroy them are shown below:
 

[] Destroy all skimmers. The PGC player places five skimmers at different locations on the map. The creature can destroy a skimmer simply by moving into the same space with it. Player characters can drive skimmers but the skimmers can not be driven off the map.

I'm not overly fond of Zeb's Guide...nor do I have any qualms stating why. 

My SF website

Same chance to hit...but how about STR/STA and DEX/RS limitations for each class? That way it will flesh out each distinct type of robot...a Guardian (security) robot could have high DEX/RS allowances but not as high in STR/STA, while a Sentry (combat) could have high STR/STA but not as high in DEX/RS. That would echo the Expanded rules of max LVL:4 for combat and max LVL:6 security in a way.

A labor bot (service) wouldn't really need high scores in either, while a worker (maintenace) could have high STR/STA but low DEX/RS so that neither becomes an effective "fighter robot" if desired.

I'm not overly fond of Zeb's Guide...nor do I have any qualms stating why. 

My SF website

Good ideas.