As a general rule, linear trackers with a properly aligned cartridge are much better at dealing with problems in vinyl.
As far as cantilever deflection goes, that will have to do with the severity of the warp. An abrupt rise will surely result in cantilever deflection, regardless of how well the arm and cartridge are dialed in and matched to each other.
Since the cantilever is the bridge between the contact area of the diamond and the pivot of the tonearm, you would have to transfer enough energy from the diamond into the cantilever to cause the suspension of the tonearm at the pivot to react accordingly. Since direct physical transfer of energy is what is taking place, it is only natural that the cantilever itself would deflect prior to passing that energy onto the arm, causing it to respond. After all, if a severe change in vertical terrain doesn't cause cantilever deflection, how could those microscopic modulations within the groove deflect it enough to produce a signal ?
If this is what you are running into, you need to either get rid of the record and / or find a way to reduce the severity of the warp. There is nothing known to man short of the "Laser Turntable" that will play severely warped records. Even with a vacuum platter and linear tracking, i won't attempt to play something that is severely warped. If you are running into this with anything less than severe warps, either something isn't dialed in correctly and / or your arm & cartridge aren't that great of a match.
As to your question pertaining to swapping arms / varying arm mass, lower mass arms won't work any better than medium mass arms if the cartridge is properly matched to the arm in use and the entire assembly is properly dialed in. What going to a lower mass arm will do is provide you with a far more limited selection of suitable cartridges to use. Most MC cartridges will not work optimally in a very low mass arm, so you would probably end up with a high compliance MM ( Moving Magnet ) or MI ( Moving Iron aka "variable reluctance" ) type of cartridge. As such, sticking with a medium mass arm and finding a suitable candidate in terms of a cartridge would offer you the most versatility for future use. Then again, MM cartridges will probably be in production longer than MC cartridges due to higher output levels and wider use by non-audiophiles. There are quite a few good MM cartridges out there, but not all of them will work real well with a low mass arm.
As a side note, cartridges like the Shure or various Stanton's and Pickering's with a "brush" act as a "dynamic shock absorber". As such, tracking can be improved but you run into other problems with this approach. Whether or not one finds this to be a worthwhile trade-off is an individual preference. Having said that, one could own / use such a cartridge with the brush lifted or removed and then take advantage of the improved tracking / damping characteristics of the brush on an as needed basis. Obviously, one has to adjust such things as the tracking force when switching between brush / no brush, but that is typically a simple matter on most arms. Sean