The Tiger 60 is probably a decent entry level Pattern Flyer as such but I think there are much better flying choices to be made such as the various Kaos series and sizes of kits by Bridi. Even though Joe Bridi is out of business there are still many of his well known and well proven designed Pattern kits still easily available on the net or even here on RCU
in the market place. He made many Kaos variants which were famous and successful Pattern Contenders.

Pumps are generally used on engines that either have poorly designed carbs OR as a manner of relocating fuel tanks to the CG to minimize trim changes during a flight when fuel is burned off making the nose lighter and the tail heavier. Engines manufactured with internal or backplate mounted pumps suit these applications well. Pumped engines also seem to work better in situations where they are inverted compared with non pumped engines.

If you decide to stay with the Tiger 60 then any reliable 60 size 2 stroke 0r 90 size 4 stroke will be more than adequate but since the Tiger 60 is a"cheek cowl" design you will need to modify the cheeks
by partial or complete removal if you want the engine in other than straight up and down configuration or are considering the use of a Pitts style exhaust but remember Pitts systems are designed mainly for fully cowled appications and can sometimes make an engine hard to tune so it runs reliably and you absolutely require a reliable engine for Pattern flying.

There are lots of really nice 60-90 size Pattern ARFs out now - take your pick.