The battery is fully exposed. The terminals easy to get to, so no worries there.
In my opinion, you can't do better than a Ctek charger. I use mine for all my rides including my power hungry 8 series, each with two huge batteries in the trunk. Never had an issue. I've also used the Ctek in the rover already to top off the battery. Couldn't be happier.
The best way to handle this if you are going to be doing this regularly is to go with the Ctek and attach the screw terminals to the battery permanently. This only takes a few minutes to do and you only need to do it once.
This way you just plug in and unplug the charger very quickly every time you want to use it. Personally, I always leave the hood open when charging so I don't forget I'm charging and rip the wires out as I drive away.
Don’t know about newer Rovers, but BMW era ones have a positive and negative posts right under the hood on the left (driver) side of the car that you can connect to, if going to the battery directly isn’t your thing. I second everyone’s sentiments regarding CTEK chargers, well worth it.
You do not want a " trickle charger". You need a fully automatic battery maintenance box. Make sure to install it direct to the battery NOT jumper posts. ANY resistance in remote cables will render the maintenance feedback useless. Most maintenance boxes come with only 14 gauge wiring and open loop generic crimps. simple mount the box away from the engine, like behind the grill run the 110/120 volt "extension cord" to an easy to access position. I mount mine in the left or right front corner of the hood when you pull the hood release you can easily have 6-8 inches of the power cord rolled up with a velcro binding strap