Let us firstly assume you've done your homework and are aware of the additional taxes and fees to be paid

What do you actually like to do ? What types of places have you enjoyed before ? Weather ?

Be aware of two things. If you limit your connection time in the UK to less than 24 hours, you'll avoid the UK govt APD tax.

Secondly, you may want to avoid a flight into LGW if you are continuing on from LHR, although that may a secondary consideration to actual availability.

My personal recommendation would be the Middle East ... in particular Oman, but the weather will be warming up, depending how you define 'spring'. You could combine this with Dubai and/or Abu Dhabi.

hth