there are alot of very lightweight actuators... there is no need to use the old style heavy metal solenoid when you can use the small 1" actuators that are now available. You can also use a pull cable if you want to move the actuator completely out of the way...
TheViper and I have looked into actuators from many different sources (industrial, automotive, RC, etc.) and we always find they won't work for some reason or another. Most are physically too large, do not have the correct stroke length, are the wrong voltage, are too weak or too powerful, are not heat rated for the temps in the engine compartment, are too expensive, or have other reasons they will not work. We even looked at using a remote actuator with a cable, but there is also the configuration of the present bracket and linkage to the latch that is difficult to address along with it being mounted to the engine lid. After examining all the potential possibilities, there is really no way to economically retrofit the present latch release assembly with an actuator unless extensive modifications to the original parts are done or a purpose built assembly is designed. We wanted to go with something simple and reliable that could be installed into the existing latch assembly, could be installed by the typical DIY guy using normal household tools, and would be relatively inexpensive to sell as a kit. In the end, the OEM design just does not allow for an easy installation/modification. I have an entire center spine from a trunk lid complete with the latch assembly still in it that I was using for mock ups just sitting here gathering dust, so I would be more than willing to take a look at it again if you have a source for actuators that we have not seen.